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This Month’s Apple Updates Fix Mavericks and iTunes Security Flaws

As much as Apple would like you to think otherwise, their products are not immune to security vulnerabilities. If you use OS X Mavericks or iTunes, you’d best update.

This week, Apple released two security updates to fix vulnerabilities in OS X Mavericks and iTunes. The updates fix a wide range of vulnerabilities, including memory corruption flaws attackers could use to execute code. If you use OS X Mavericks or iTunes, you should download and install Apple’s updates immediately, or let their automatic Software Updater do it for your.

See the links below for more information about each update:

If you’d like to keep up with Apple’s latest security updates, be sure to bookmark their Security page, and you can find links to all their patches on the Download page.— Corey Nachreiner, CISSP (@SecAdept)

Four Windows Bulletins Fix Group Policy, .NET, and iSCSI Flaws

Severity: Medium

Summary:

  • These vulnerabilities affect: All current versions of Windows (and related components like .NET Framework)
  • How an attacker exploits them: Multiple vectors of attack, though most require authenticated attackers to do things locally
  • Impact: In the worst case, an authenticated attacker can gain complete control of your Windows computer
  • What to do: Install the appropriate Microsoft patches as soon as possible, or let Windows Automatic Update do it for you

Exposure:

Today, Microsoft released four security bulletins describing five vulnerabilities in Windows and related components, such as the .NET Framework. An authenticated attacker could exploit the worst of these flaws to potentially gain complete control of your Windows PC. We recommend you download, test, and deploy these critical updates as quickly as possible.

The summary below lists the vulnerabilities, in order from highest to lowest severity.

  • MS14-025: Group Policy Preferences Password Elevation of Privilege Flaw

Group Policy is the Windows feature that allows administrators to push configuration and settings to other Windows computers throughout their network. Group Policy Preferences are simply an extension of settings you can push via Group Policy. Microsoft’s alert describes a vulnerability in the way Active Directory sends password information with certain Group Policy Preferences. If you use Group Policy to set system administrator accounts, map drives, or run scheduled tasks—all things that require privileges—Group Policy stores an encrypted version of the password or credential needed for this task on the local computer. Local, authenticated attackers can then use that information to crack the password, and perhaps elevate their privileges. For instance, if you use your domain administrator account to run a particular scheduled task on every Windows computer network when it boots, local Windows users may have the information they need to crack your domain administrator account. That said, attackers would need valid credentials to log into one of your windows computers in order to exploit this flaw. So this primarily poses an insider risk.

Microsoft rating: Important

  • MS14-026:  .NET Framework Elevation of Privilege Vulnerability

The .NET Framework is a software framework used by developers to create custom Windows and web applications. Though it only ships by default with Windows Vista, you’ll find it on many Windows computers.

The .NET Framework suffers from an unspecified elevation of privilege vulnerability. If an authenticated attacker can send specially crafted data to an app that uses .NET Remoting, he can exploit this flaw to execute code on that system with full system privileges.

Microsoft rating: Important

  • MS14-027:  Windows Shell Elevation of Privilege Vulnerability

The Windows Shell is the primary GUI component for Windows. It suffers from a vulnerability having to do with its ShellExecute Application Programming Interface (API). If a local attacker can log in to one of your Windows systems and run a specially crafted program, he can exploit this flaw to execute code with local administrator privileges, thus gaining full control of the computer.

Microsoft rating: Important

  • MS14-028:  Two iSCSI DoS Vulnerabilities

iSCSI is a standard that supports network based storage devices. The Windows iSCSI component suffers from two Denial of Service (DoS) vulnerabilities. By sending a large amount of specially crafted packets to the iSCSI service (TCP 3260), an attacker could exploit this flaw to cause the iSCSI service to stop responding. Of course, the attacker needs access to the iSCSI service, which most administrator might block with their firewall.

Microsoft rating: Important

Solution Path:

Microsoft has released various updates that correct all of these vulnerabilities. You should download, test, and deploy the appropriate updates throughout your network immediately. If you choose, you can also let Windows Update automatically download and install them for you. As always, you should test your updates before deploying them. I especially recommend you test the Group Policy Preference update before deploy it, as it may slightly change the way Group Policy Preferences work.

The links below point directly to the “Affected and Non-Affected Software” section of each bulletin, where you can find links to the various updates:

For All WatchGuard Users:

Though WatchGuard’s XTM appliances offer defenses that can mitigate the risk of some of these flaws (such as blocking TCP port 3260), attackers can exploit others locally. Since your gateway XTM appliance can’t protect you against local attacks, we recommend you install Microsoft’s updates to completely protect yourself from these flaws.

Status:

Microsoft has released patches correcting these issues.

References:

This alert was researched and written by Corey Nachreiner, CISSP (@SecAdept).


What did you think of this alert? Let us know at your.opinion.matters@watchguard.com.

Office Updates Include Patches for SharePoint Vulnerabilities

Severity: High

Summary:

  • These vulnerabilities affect: Microsoft Office and related products like SharePoint Server
  • How an attacker exploits them: Varies. Typically by enticing users to open or interact with maliciously crafted Office documents, or interacting with web resources
  • Impact: Many. In the worst case, an attacker can gain complete control of your Windows computer
  • What to do: Install the appropriate Microsoft patches as soon as possible, or let Windows Automatic Update do it for you

Exposure:

Today, Microsoft released three security bulletins that fix a number of vulnerabilities in Office, SharePoint, and related components. We summarize these security bulletins below, in order from highest to lowest severity.

  • MS14-022: Multiple SharePoint Vulnerabilities

SharePoint Server is Microsoft’s web and document collaboration and management platform. SharePoint, and some of its related components, suffer from both multiple remote code execution vulnerabilities and a cross-site scripting (XSS) flaw. The remote code execution flaws pose the most risk, and involve several unspecified input sanitation vulnerabilities in a number of SharePoint pages. If an authenticated attacker can upload specially crafted content to your SharePoint server, he could leverage this flaw to execute code on that server with the W3WP (w3wp.exe) service account’s privileges. Unfortunately, Microsoft’s alert doesn’t go into detail about the privileges associated with the W3WP services account. However, we’ve found that w3wp.exe often runs as a child process under svchost.exe, which runs with local SYSTEM privileges by default; potentially making this a complete system compromise. If you run SharePoint servers, you should patch this as quickly as you can.

Microsoft rating: Critical

  • MS14-023: Office Remote Code Execution Flaw

Various Office components suffer from two publicly reported vulnerabilities. The worst is a remote code execution flaw involving the way Office’s “Grammar Checker” feature loads Dynamic Link Libraries (DLL). However, the flaw only affects Grammar Checker when the language is set to Chinese (Simplified). If a remote attacker can convince you to open an Office document that resides in the same directory (local or over a network) as a malicious DLL, she could exploit this flaw to execute code with your privileges. If you have local administrative access, the attacker gains complete control of your computer. However, this flaw will likely primarily affect Chinese Office users, which somewhat limits its impact. Office also suffers from something call a “token reuse” flaw, but it poses a lesser risk that the remote code execution one.

Microsoft rating: Important

  • MS13-086 MCCOMCTL ASLR Bypass Vulnerabilities

Office (and many other Microsoft products) ships with a set of ActiveX controls that Microsoft calls the Windows Common Controls (MSCOMCTL.OCX). Address Space Layout Randomization (ASLR) is a memory obfuscation technique that some operating systems use to make it harder for attackers to find specific things in memory, which in turn makes it harder for them to exploit memory corruption flaws. Office’s MSCOMCTL component doesn’t enable ASLR protection. This means attackers can leverage this particular component to bypass Windows’ ASLR protection features. This flaw alone doesn’t allow an attacker to gain access to your Windows computer. Rather, it can help make other memory corruption vulnerabilities easier to exploit. This update fixes the ASLR bypass hole.

Microsoft rating: Important

Solution Path:

Microsoft has released Office and SharePoint-related patches that correct all of these vulnerabilities. You should download, test, and deploy the appropriate updates throughout your network as soon as possible. If you choose, you can also let Windows Update automatically download and install these updates for you.

Keep in mind, however, that we highly recommend you test updates before running them in your production environment; especially updates for critical production servers.

The links below point directly to the “Affected and Non-Affected Software” section of each bulletin, where you can find all of Microsoft’s update links:

For All WatchGuard Users:

WatchGuard’s eXtensible Threat Management (XTM) security appliances can help mitigate the risk of some of these vulnerabilities. Gateway Antivirus and Intrusion Prevention services can often prevent some of these types of attacks, or the malware these types of attacks try to distribute. Nonetheless, we still recommend you install Microsoft’s updates to completely protect yourself from these flaws.

Status:

Microsoft has released patches correcting these issues.

References:

This alert was researched and written by Corey Nachreiner, CISSP (@SecAdept).


What did you think of this alert? Let us know at your.opinion.matters@watchguard.com.

May’s IE Update Corrects Two New Memory Corruptions

Summary:

  • This vulnerability affects: All current versions of Internet Explorer
  • How an attacker exploits it: By enticing one of your users to visit a web page containing malicious content
  • Impact: Various, in the worst case an attacker can execute code on your user’s computer, potentially gaining complete control of it
  • What to do: Deploy the appropriate Internet Explorer patches immediately, or let Windows Automatic Update do it for you

Exposure:

In a security bulletin released today as part of Patch Day, Microsoft describes two new vulnerabilities that affect all current versions of Internet Explorer (IE). Microsoft rates the aggregate severity of these new flaws as Critical.

Though the two vulnerabilities differ technically, they share the same general scope and impact, and involve memory corruption flaws having to do with how IE handles certain HTML objects. If an attacker can lure one of your users to a web page containing malicious web code, he could exploit either of these memory corruption vulnerabilities to execute code on that user’s computer, inheriting that user’s privileges. Typically, Windows users have local administrative privileges. In that case, the attacker could exploit these flaws to gain complete control of the victim’s computer.

Technical differences aside, the memory corruption flaws in IE pose significant risk. You should download and install the IE cumulative patch immediately. Also note, this IE cumulative patch also includes a fix for the zero day IE flaw Microsoft fixed earlier, in an out-of-cycle update. If, for some reason, you haven’t applied that update yet, this is a good time to fix that serious zero day flaw.

Keep in mind, today’s attackers often hijack legitimate web pages and booby-trap them with malicious code. Typically, they do this via hosted web ads or through SQL injection and cross-site scripting (XSS) attacks. Even recognizable and authentic websites could pose a risk to your users if hijacked in this way, and the vulnerabilities described in today’s bulletin are perfect for use in drive-by download attacks.

Solution Path:

You should download, test, and deploy the appropriate IE updates immediately, or let Windows Automatic Update do it for you. You can find links to the various IE updates in the “Affected and Non-Affected Software” section of Microsoft’s April IE security bulletin.

For All WatchGuard Users:

Good News! WatchGuard’s Gateway Antivirus and Intrusion Prevention services can often prevent these sorts of attacks, or the malware they try to distribute. For instance, our IPS signature team has developed signatures that can detect and block the memory corruption vulnerabilities described in Microsoft’s alert:

  • WEB-CLIENT Microsoft Internet Explorer Memory Corruption Vulnerability (CVE-2014-0310)
  • WEB-CLIENT Microsoft Internet Explorer Memory Corruption Vulnerability (CVE-2014-1815)

Your XTM appliance should get this new IPS 4.414 signature update shortly.

Furthermore, our Reputation Enabled Defense (RED) and WebBlocker services can often prevent your users from accidentally visiting malicious (or legitimate but booby-trapped) web sites that contain these sorts of attacks. Nonetheless, we still recommend you install Microsoft’s updates to completely protect yourself from all of these flaws.

Status:

Microsoft has released patches to fix these vulnerabilities.

References:

This alert was researched and written by Corey Nachreiner, CISSP (@SecAdept).

Microsoft Black Tuesday: Patches for IE, Sharepoint, Office, and Windows

Calling all Microsoft administrators! It’s Microsoft Patch Day, and their security updates are available for download.

You know the drill by now. As they do every second Tuesday of the month, Microsoft has released May’s important security updates. You can find this month’s Patch Day highlights in Microsoft’s summary post, but here’s what you really need to know:

  • Microsoft released eight bulletins, two rated Critical and the rest Important.
  • The affected products include
    • Windows
    • Office
    • Internet Explorer (IE)
    • and Sharepoint Server.
  • Attackers are apparently exploiting some of the Windows and IE vulnerabilities in the wild already, in what Microsoft calls “limited, targeted attacks.
  • As expected, Windows XP users aren’t getting patches this month (or from hereafter).

In short, if you use any of the affected Microsoft products, you should download, test, and deploy these updates as quickly as you can. You can also let Windows’ Automatic Update do it for you. While I don’t recommend Automatic Update on servers (due to potential patch bugs), I do think you should enable it on your clients computers. As always, concentrate on installing the Critical updates as soon as you can (especially the IE one this month), and handle the others later.

I’ll share more details about today’s patches on the blog throughout the day, though these posts may be slightly delayed due to my participation in WatchGuard’s US Partner Summit.  — Corey Nachreiner, CISSP (@SecAdept).

Adobe Patch Day: Reader, Flash, and Illustrator Security Patches

Severity: High

Summary:

  • These vulnerabilities affect: Reader and Acrobat, Flash Player, and Illustrator (CS6)
  • How an attacker exploits them: Multiple vectors of attack, including enticing your users to open malicious files or visit specially crafted web sites
  • Impact: Various results; in the worst case, an attacker can gain complete control of your computer
  • What to do: Install the appropriate Adobe patches immediately, or let Adobe’s updater do it for you.

Exposure:

Today, Adobe released or updated three security bulletins that describe vulnerabilities in four of their popular software packages; Reader and Acrobat X, Flash Player, and Illustrator.

Adobe Patch Day, May 2014

 

A remote attacker could exploit the worst of these flaws to gain complete control of your computer. We summarize the Adobe security bulletins below:

  • APSB14-15: Multiple Reader and Acrobat Code Execution Vulnerabilities

Adobe Reader helps you view PDF documents, while Acrobat helps you create them. Since PDF documents are very popular, most users install Reader to handle them.

Adobe’s bulletin describes 11 vulnerabilities that affect Adobe Reader and Acrobat XI 11.0.06 and earlier, running on Windows and Macintosh.  Adobe only describes the flaws in minimal technical detail, but they do share that many of the flaws involve memory corruption issues that attackers could exploit to execute code. Most of these memory corruption flaws share the same scope and impact. If an attacker can entice one of your users into opening a specially crafted PDF file, he can exploit these issues to execute code on that user’s computer, inheriting the user’s privileges. If your users have root or system administrator privileges, the attacker gains complete control of their computer. If you use Reader, you should patch soon.

Adobe Priority Rating: 1 (Patch within 72 hours)

  • APSB14-14: Half a Dozen Flash Player (and Air) Vulnerabilities

Adobe Flash Player displays interactive, animated web content called Flash. Although Flash is optional, 99% of PC users download and install it to view multimedia web content. It runs on many operating systems, including mobile operating systems like Android. It is also built into certain browsers, like Google and Internet Explorer (IE) 11.

Adobe’s bulletin describes six flaws in Flash Player 13.0.0.206 and earlier for all platforms. The vulnerabilities differ technically, and in scope and impact, but the worst could allow attackers to execute code on your users computers. Specifically, Flash Player suffers from a “use after free” vulnerability – a type of memory corruption flaw that attackers can leverage to execute arbitrary code. If an attacker can lure you to a web site, or get you to open documents containing specially crafted Flash content, he could exploit this flaw to execute code on your computer, with your privileges. If you have administrative or root privileges, the attacker could gain full control of your computer. Though not as severe as the use after free flaw, the remaining flaws are all security bypass issues that could also help attackers further elevate their privileges after an attack.

Adobe Priority Rating: 1 (Patch within 72 hours)

  • APSB14-011: Illustrator (CS6) Buffer Overflow Vulnerability

Illustrator is a very popular vector drawing program that ships with Adobe’s popular Creative Suite. It suffers from an unspecified buffer overflow vulnerability. Adobe doesn’t describe the flaw in technical detail, but we presume that it has something to do with handling specially crafted Illustrator files. If that’s the case, opening specially crafted files in Illustrator could allow attackers to execute code on your machine with your privileges. Attackers don’t often target Illustrator, so we don’t expect this vulnerability to get exploited much in the wild. Nonetheless, if you use Illustrator, you ought to patch it at your convenience.

Adobe Priority Rating: 3 (Patch at your discretion)

Solution Path:

Adobe has released updates for all their affected software. If you use any of the software below, we recommend you download and deploy the corresponding updates as soon as possible, or let Adobe’s automatic updater do it for you.

For All WatchGuard Users:

Attackers can exploit these flaws using diverse exploitation methods. Installing Adobe’s updates is your most secure course of action.

Status:

Adobe has released patches correcting these issues.

References:

    • Adobe Reader/Acrobat Security Update APSB14-15
    • Adobe Flash Player Security Update APSB14-14
    • Adobe Illustrator Security Update APSB14-11

This alert was researched and written by Corey Nachreiner, CISSP (@SecAdept).

May Brings Eight Microsoft Bulletins and One Adobe Update

Patch Day is coming, Patch Day is coming.

In their advanced notification yesterday, Microsoft announced they’d release eight security bulletins next Tuesday to fix security vulnerabilities in a number of their products. The bulletins will include updates for Internet Explorer (IE), Windows, Office, and a yet unnamed Microsoft Server product. They give two of the bulletins a Critical rating, and the rest listed as Important. See the chart below for complete details.

As usual, Adobe shares the same Patch Day and plans to released one update as well. According to their prenotification post, Adobe plans to released a patch for Adobe Reader and Acrobat, which will fix a serious vulnerabilities in the popular PDF reader. They’ve assigned it a priority of 1 (their highest), so you should plan to apply the patch quickly if you use Reader.

In short, if you’re a Microsoft administrator, or you use Adobe products, be ready to test and deploy a number of updates next week. As always, you should start with the critical updates, and work your way down through the less severe ones. I’ll post details about all these bulletins next week, so stay tuned. — Corey Nachreiner, CISSP (@SecAdept)

MS Patch Day, May 2014

UPDATE TO: Advanced Attackers Exploit IE 0day in the Wild

Severity: High

Summary:

  • This vulnerability affects: All versions of Internet Explorer (IE)
  • How an attacker exploits it: By enticing a user to visit web site containing malicious content
  • Impact: An attacker can execute code with your privileges, potentially gaining complete control of your computer
  • What to do: Install Microsoft’s emergency IE patch immediately, or let Windows Update do it for you

Exposure:

On Monday, we released an alert warning about a zero day vulnerability affecting all version of Internet Explorer. Researchers discovered attackers exploiting this critical flaw in the wild, and Microsoft had not yet released a patch at that time.

Today, Microsoft released an out-of-cycle security bulletin containing an update to fix this serious vulnerability. As mentioned in our original alert, IE suffers from something called a “use after free” memory corruption vulnerability. By enticing one of your users to a web site containing malicious content, an attacker can exploit this flaw to execute code on your machine, with your privileges. As usual, if you have local administrator privileges, the attacker gains full control of your machine.

Keep in mind, today’s attackers often hijack legitimate web pages and booby-trap them with malicious code. Typically, they do this via hosted web ads or through SQL injection and cross-site scripting (XSS) attacks. Even recognizable and authentic websites could pose a risk to your users if hijacked in this way, and the vulnerabilities described in today’s bulletin are perfect for use in drive-by download attacks. Furthermore, attackers are already exploiting this particular flaw in targeted attacks. We highly recommend you install Microsoft’s IE update immediately

We have included the original alert below for your convenience.

Solution Path:

Microsoft has released IE updates to correct this vulnerability. You should download, test, and deploy the updates immediately, or let Windows Update do it for you. You can find the updates in the “Affected and Non-Affected Software” section of Microsoft’s IE bulletin. Also note, Microsoft has included updates for Windows XP customers, despite their End-of-Life date last month.

If for some reason you cannot patch immediately, there are also some workarounds than can mitigate the issue. We detail those workarounds in our original alert, which we’ve included below for your convenience.

For All WatchGuard Users:

As mentioned in our original alert, there are a number of things WatchGuard XTM customers can do to protect themselves. For instance, you can use our proxy policies to block Flash content by extension (.SWF) or by MIME type (application/x-shockwave-flash). Furthermore, our IPS service includes signatures that block this IE exploit (update to signature set 4.410). Nonetheless, we still highly recommend you install Microsoft’s IE update to completely protect yourself from this attack.

Status:

Microsoft has released patches to fix this vulnerability.

References:

This alert was researched and written by Corey Nachreiner, CISSP (@SecAdept).


Over the weekend, Microsoft released a critical security advisory warning customers of a serious new zero day vulnerability in Internet Explorer (IE), which attackers are exploiting in the wild. Around the same time, Kaspersky also noted an attack campaign leveraging a new Adobe Flash zero day flaw, which Adobe patched today. I’ll discuss both issues below, starting with the IE issue.

IE Zero Day in the Wild

According to this blog post, researchers at FireEye discovered advanced attackers exploiting this zero day IE flaw as part of a persistent attack campaign they are calling “Operation Clandestine Fox.” The attack targets IE 9-11 and also leverages a Flash flaw to help bypass some of Windows’ security features.

Shortly after FireEye’s post, Microsoft released a security advisory confirming the previously undiscovered flaw in IE. The advisory warns that the flaw affects all versions of IE (though the attack seems to target IE 9-11). While Microsoft is still researching the issue, the vulnerability seems to be a “use after free” class of memory corruption vulnerability. In short, if an attacker can entice you to a web page containing maliciously crafted content, he could exploit this flaw to execute code on your machine, with your privileges. As usual, if you have local administrator privileges, the attacker would gain full control of your machine. It’s interesting to note, the attackers also leverage a known Adobe Flash issue to help defeat some of Microsoft’s Windows memory protection features.

Zero day IE vulnerabilities are relatively rare, and very dangerous. Attackers are already exploiting this IE one in the wild, so it poses a significant risk. Unfortunately, Microsoft just learned of the flaw, so they haven’t had time to patch it yet. I suspect Microsoft will release an out-of-cycle patch for this flaw very shortly since this is a high-profile issue. In the meantime here a few workarounds to help mitigate the flaw:

  • Temporarily use a different web browser – I’m typically not one to recommend one web browser over another, as far as security is concerned. They all have had vulnerabilities. However, this is a fairly serious issue.  So you may want to consider temporarily using a different browser until Microsoft patches.
  • Install Microsoft EMETEMET is an optional Microsoft tool that adds additional memory protections to Windows. I described EMET in a previous episode of WatchGuard Security Week in Review. Installing EMET could help protect your computer from many types of memory corruption flaws, including this one. This Microsoft blog post shares more details on how it can help with this issue.
  • Configure Enhanced Security Configuration mode on Windows Servers – Windows Servers in Enhanced Security Configuration mode are not vulnerable to many browser-based attacks.
  • Disable VML in IE – This exploit seems to rely on VML to work. Microsoft released a blog post detailing how disabling VML in IE, or running IE in “Enhanced Protection Mode” can help.
  • Make sure your AV and IPS is up to date – While not all IPS and AV systems have signatures for all these attacks yet, they will in the coming days. In fact, WatchGuard’s IPS engineers have already created signatures to catch this attack. We are QA testing the signatures now, but they should be available to XTM devices shortly. Whatever IPS system you use, be sure to keep your AV and IPS systems updating regularly, to get the latest protections.
  • WatchGuard XTM customers can block Flash with proxies - If you own a WatchGuard XTM security appliance, you can use our proxy policies to block certain content, including Flash content. For instance, you can use our SMTP or HTTP proxies to block SWF files by extensions (.SWF) or by MIME type (application/x-shockwave-flash). Keep in mind, blocking Flash blocks both legitimate and malicious content. So only implement this workaround if you are ok with your users not accessing normal Flash pages.

Adobe Patches Flash Zero Day

Coincidentally, Adobe also released an emergency Flash update today fixing a zero day exploit that other advanced attackers are also exploiting in a targeted watering hole campaign. The patch fixes a single vulnerability in the popular Flash media player, which attackers could exploit to run arbitrary code on your system; simply by enticing you to a web site containing specially crafted Flash content. This exploit was discovered in the wild by Kaspersky researchers (one of our security partners). According to Kaspersky’s research, the exploit was discovered on a Syrian website, and seems to be designed to target potential Syrian dissidents.

The good news is there is a patch for this flaw. So if you use Adobe Flash, go get the latest update now. By the way, some browsers like Chrome and IE 11 embed Flash directly, so you will also have to update those browsers individually. Finally, though the IE zero day I mentioned earlier does rely on a Flash issue, this particular zero day Flash flaw is totally unrelated. One additional note; WatchGuard’s IPS engineers have also created a signature for this exploit as well. It will be available shortly, once testing is complete.

So to summarize, if you use IE, disable VML, install EMET, and watch for an upcoming patch. If you use Flash, updates as soon as you can. I will be sure to inform you here, as soon as Microsoft releases their real patch or FixIt. — Corey Nachreiner, CISSP (@SecAdept)

Advanced Attackers Exploit IE & Flash 0days in the Wild

Over the weekend, Microsoft released a critical security advisory warning customers of a serious new zero day vulnerability in Internet Explorer (IE), which attackers are exploiting in the wild. Around the same time, Kaspersky also noted an attack campaign leveraging a new Adobe Flash zero day flaw, which Adobe patched today. I’ll discuss both issues below, starting with the IE issue.

IE Zero Day in the Wild

According to this blog post, researchers at FireEye discovered advanced attackers exploiting this zero day IE flaw as part of a persistent attack campaign they are calling “Operation Clandestine Fox.” The attack targets IE 9-11 and also leverages a Flash flaw to help bypass some of Windows’ security features.

Shortly after FireEye’s post, Microsoft released a security advisory confirming the previously undiscovered flaw in IE. The advisory warns that the flaw affects all versions of IE (though the attack seems to target IE 9-11). While Microsoft is still researching the issue, the vulnerability seems to be a “use after free” class of memory corruption vulnerability. In short, if an attacker can entice you to a web page containing maliciously crafted content, he could exploit this flaw to execute code on your machine, with your privileges. As usual, if you have local administrator privileges, the attacker would gain full control of your machine. It’s interesting to note, the attackers also leverage a known Adobe Flash issue to help defeat some of Microsoft’s Windows memory protection features.

Zero day IE vulnerabilities are relatively rare, and very dangerous. Attackers are already exploiting this IE one in the wild, so it poses a significant risk. Unfortunately, Microsoft just learned of the flaw, so they haven’t had time to patch it yet. I suspect Microsoft will release an out-of-cycle patch for this flaw very shortly since this is a high-profile issue. In the meantime here a few workarounds to help mitigate the flaw:

  • Temporarily use a different web browser – I’m typically not one to recommend one web browser over another, as far as security is concerned. They all have had vulnerabilities. However, this is a fairly serious issue.  So you may want to consider temporarily using a different browser until Microsoft patches.
  • Install Microsoft EMETEMET is an optional Microsoft tool that adds additional memory protections to Windows. I described EMET in a previous episode of WatchGuard Security Week in Review. Installing EMET could help protect your computer from many types of memory corruption flaws, including this one. This Microsoft blog post shares more details on how it can help with this issue.
  • Configure Enhanced Security Configuration mode on Windows Servers – Windows Servers in Enhanced Security Configuration mode are not vulnerable to many browser-based attacks.
  • Disable VML in IE – This exploit seems to rely on VML to work. Microsoft released a blog post detailing how disabling VML in IE, or running IE in “Enhanced Protection Mode” can help.
  • Make sure your AV and IPS is up to date – While not all IPS and AV systems have signatures for all these attacks yet, they will in the coming days. In fact, WatchGuard’s IPS engineers have already created signatures to catch this attack. We are QA testing the signatures now, but they should be available to XTM devices shortly. Whatever IPS system you use, be sure to keep your AV and IPS systems updating regularly, to get the latest protections.
  • WatchGuard XTM customers can block Flash with proxies - If you own a WatchGuard XTM security appliance, you can use our proxy policies to block certain content, including Flash content. For instance, you can use our SMTP or HTTP proxies to block SWF files by extensions (.SWF) or by MIME type (application/x-shockwave-flash). Keep in mind, blocking Flash blocks both legitimate and malicious content. So only implement this workaround if you are ok with your users not accessing normal Flash pages.

Adobe Patches Flash Zero Day

Coincidentally, Adobe also released an emergency Flash update today fixing a zero day exploit that other advanced attackers are also exploiting in a targeted watering hole campaign. The patch fixes a single vulnerability in the popular Flash media player, which attackers could exploit to run arbitrary code on your system; simply by enticing you to a web site containing specially crafted Flash content. This exploit was discovered in the wild by Kaspersky researchers (one of our security partners). According to Kaspersky’s research, the exploit was discovered on a Syrian website, and seems to be designed to target potential Syrian dissidents.

The good news is there is a patch for this flaw. So if you use Adobe Flash, go get the latest update now. By the way, some browsers like Chrome and IE 11 embed Flash directly, so you will also have to update those browsers individually. Finally, though the IE zero day I mentioned earlier does rely on a Flash issue, this particular zero day Flash flaw is totally unrelated. One additional note; WatchGuard’s IPS engineers have also created a signature for this exploit as well. It will be available shortly, once testing is complete.

So to summarize, if you use IE, disable VML, install EMET, and watch for an upcoming patch. If you use Flash, updates as soon as you can. I will be sure to inform you here, as soon as Microsoft releases their real patch or FixIt. — Corey Nachreiner, CISSP (@SecAdept)

Apple Releases Critical OS X, iOS, and Apple TV Patches

Hey Apple users; it’s time to patch.

This week, Apple released three security updates to fix vulnerabilities in OS X, iOS, and Apple TV. The updates fix a wide range of vulnerabilities, including memory corruption flaws attackers could use to execute code, and something called a “triple handshake attack,” which attackers could leverage in man-in-the-middle (MitM) attacks against your SSL sessions. If you use OS X, iOS, or Apple TV, you should download and install Apple’s updates immediately, or let their automatic Software Updater do it for your.

See the links below for more information about each update:

If you’d like to keep up with Apple’s latest security updates, be sure to bookmark their Security page, and you can find links to all their patches on the Download page.

In a related note, Kristin Paget, an ex-Apple security researcher, published a blog post criticizing Apple’s patching process. Apparently, Apple had already released updates to OS X previously that fix the same Webkit vulnerabilities that iOS 7.1.1. fixes this month. Paget argues that Apple needs to release all the like fixes at the same, otherwise attackers could reverse the patches from OS X to exploit against iOS, or vice versa. This is good advice, which I hope Apple adopts in the future — Corey Nachreiner, CISSP (@SecAdept)

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