Posts Tagged: Chris Goettl

Apr 16

‘Badlock’ Bug Tops Microsoft Patch Batch

Microsoft released fixes on Tuesday to plug critical security holes in Windows and other software. The company issued 13 patches to tackle dozens of vulnerabilities, including a much-hyped “Badlock” file-sharing bug that appears ripe for exploitation. Also, Adobe updated its Flash Player release to address at least two-dozen flaws — in addition to the zero-day vulnerability Adobe patched last week.



The Windows patch that seems to be getting the most attention this month remedies seven vulnerabilities in Samba, a service used to manage file and print services across networks and multiple operating systems. This may sound innocuous enough, but attackers who gain access to private or corporate network could use these flaws to intercept traffic, view or modify user passwords, or shut down critical services.

According to, a Web site set up to disseminate information about the widespread nature of the threat that this vulnerability poses, we are likely to see active exploitation of the Samba vulnerabilities soon.

Two of the Microsoft patches address flaws that were disclosed prior to Patch Tuesday. One of them is included in a bundle of fixes for Internet Explorer. A critical update for the Microsoft Graphics Component targets four vulnerabilities, two of which have been detected already in exploits in the wild, according to Chris Goettl at security vendor Shavlik.

Just a reminder: If you use Windows and haven’t yet taken advantage of the Enhanced Mitigation Experience Toolkit, a.k.a. “EMET,” you should definitely consider it. I describe the basic features and benefits of running EMET in this blog post from 2014 (yes, it’s time to revisit EMET in a future post), but the gist of it is that EMET helps block or blunt exploits against known and unknown Windows vulnerabilities and flaws in third-party applications that run on top of Windows. The latest version, v. 5.5, is available hereContinue reading →

Nov 14

Microsoft Releases Emergency Security Update

Microsoft today deviated from its regular pattern of releasing security updates on the second Tuesday of each month, pushing out an emergency patch to plug a security hole in all supported versions of Windows. The company urged Windows users to install the update as quickly as possible, noting that miscreants already are exploiting the weaknesses to launch targeted attacks.

brokenwindowsThe update (MS14-068) addresses a bug in a Windows component called Microsoft Windows Kerberos KDC, which handles authenticating Windows PCs on a local network. It is somewhat less of a problem for Windows home users (it is only rated critical for server versions of Windows) but it poses a serious threat to organizations. According to security vendor Shavlik, the flaw allows an attacker to elevate domain user account privileges to those of the domain administrator account.

“The attacker could forge a Kerberos Ticket and send that to the Kerberos KDC which claims the user is a domain administrator,” writes Chris Goettl, product manager with Shavlik. “From there the attacker can impersonate any domain accounts, add themselves to any group, install programs, view\change\delete date, or create any new accounts they wish.  This could allow the attacker to then compromise any computer in the domain, including domain controllers.  If there is a silver lining in this one it is in the fact that the attacker must have a valid domain user account to exploit the vulnerability, but once they have done so, they have the keys to the kingdom.”

The patch is one of two that Microsoft had expected to release on Patch Tuesday earlier this month, but unexpectedly pulled at the last moment.  “This is pretty severe and definitely explains why Microsoft only delayed the release and did not pull it from the November Patch Tuesday release all together,” Goettl said. Continue reading →

Nov 14

Adobe, Microsoft Issue Critical Security Fixes

Adobe and Microsoft today each issued security updates to fix critical vulnerabilities in their software. Microsoft pushed 14 patches to address problems in Windows, Office, Internet Explorer and .NET, among other products. Separately, Adobe issued an update for its Flash Player software that corrects at least 18 security issues.

brokenwindowsMicrosoft announced 16 bulletins, but curiously two of those are listed as pending. Topping the list of critical updates from Microsoft is a fix for a zero-day vulnerability disclosed last month that hackers have been using in targeted cyber espionage attacks. Another critical patch targets 17 weaknesses in Internet Explorer, including a remotely exploitable vulnerability in all supported versions of Windows that earned a CVSS score of 9.3 (meaning it is highly likely to be exploited in drive-by attacks, and probably soon).

That flaw is a rare “unicorn-like” bug according to IBM X-Force, which discovered and reported the issue privately to Microsoft. In a blog post published today, IBM researchers described how the vulnerability can be used to sidestep the Enhanced Protected Mode sandbox in IE11, as well as Microsoft’s EMET anti-exploitation tool that Microsoft offers for free.

“In this case, the buggy code is at least 19 years old, and has been remotely exploitable for the past 18 years,” writes IBM researcher Robert Freeman. “Looking at the original release code of Windows 95, the problem is present. In some respects this vulnerability has been sitting in plain sight for a long time, despite many other bugs being discovered and patched in the same Windows library (OleAut32).”

Freeman said while unpatched Internet Explorer users are most at risk from this bug, the vulnerability also could be exploited through Microsoft Office files. “The other attack vectors this vulnerability could work with are Microsoft Office with script macros, for example in Excel documents,” Freeman told KrebsOnSecurity. “Most versions of Office (since about 2003) have macros disabled by default so the user would have to enable them (which can be a fairly mindless YES click at the top of the screen). Or if a user is using an old enough version of Office, the macros will be enabled by default.”


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