Posts Tagged: Satnam Narang


11
Aug 20

Microsoft Patch Tuesday, August 2020 Edition

Microsoft today released updates to plug at least 120 security holes in its Windows operating systems and supported software, including two newly discovered vulnerabilities that are actively being exploited. Yes, good people of the Windows world, it’s time once again to backup and patch up!

At least 17 of the bugs squashed in August’s patch batch address vulnerabilities Microsoft rates as “critical,” meaning they can be exploited by miscreants or malware to gain complete, remote control over an affected system with little or no help from users. This is the sixth month in a row Microsoft has shipped fixes for more than 100 flaws in its products.

The most concerning of these appears to be CVE-2020-1380, which is a weaknesses in Internet Explorer that could result in system compromise just by browsing with IE to a hacked or malicious website. Microsoft’s advisory says this flaw is currently being exploited in active attacks.

The other flaw enjoying active exploitation is CVE-2020-1464, which is a “spoofing” bug in virtually all supported versions of Windows that allows an attacker to bypass Windows security features and load improperly signed files. For more on this flaw, see Microsoft Put Off Fixing Zero for 2 Years.

Trend Micro’s Zero Day Initiative points to another fix — CVE-2020-1472 — which involves a critical issue in Windows Server versions that could let an unauthenticated attacker gain administrative access to a Windows domain controller and run an application of their choosing. A domain controller is a server that responds to security authentication requests in a Windows environment, and a compromised domain controller can give attackers the keys to the kingdom inside a corporate network.

“It’s rare to see a Critical-rated elevation of privilege bug, but this one deserves it,” said ZDI’S Dustin Childs. “What’s worse is that there is not a full fix available.”

Perhaps the most “elite” vulnerability addressed this month earned the distinction of being named CVE-2020-1337, and refers to a security hole in the Windows Print Spooler service that could allow an attacker or malware to escalate their privileges on a system if they were already logged on as a regular (non-administrator) user.

Satnam Narang at Tenable notes that CVE-2020-1337 is a patch bypass for CVE-2020-1048, another Windows Print Spooler vulnerability that was patched in May 2020. Narang said researchers found that the patch for CVE-2020-1048 was incomplete and presented their findings for CVE-2020-1337 at the Black Hat security conference earlier this month. More information on CVE-2020-1337, including a video demonstration of a proof-of-concept exploit, is available here. Continue reading →


12
May 20

Microsoft Patch Tuesday, May 2020 Edition

Microsoft today issued software updates to plug at least 111 security holes in Windows and Windows-based programs. None of the vulnerabilities were labeled as being publicly exploited or detailed prior to today, but as always if you’re running Windows on any of your machines it’s time once again to prepare to get your patches on.

May marks the third month in a row that Microsoft has pushed out fixes for more than 110 security flaws in its operating system and related software. At least 16 of the bugs are labeled “Critical,” meaning ne’er-do-wells can exploit them to install malware or seize remote control over vulnerable systems with little or no help from users.

But focusing solely on Microsoft’s severity ratings may obscure the seriousness of the flaws being addressed this month. Todd Schell, senior product manager at security vendor Ivanti, notes that if one looks at the “exploitability assessment” tied to each patch — i.e., how likely Microsoft considers each can and will be exploited for nefarious purposes — it makes sense to pay just as much attention to the vulnerabilities Microsoft has labeled with the lesser severity rating of “Important.”

Virtually all of the non-critical flaws in this month’s batch earned Microsoft’s “Important” rating.

“What is interesting and often overlooked is seven of the ten [fixes] at higher risk of exploit are only rated as Important,” Schell said. “It is not uncommon to look to the critical vulnerabilities as the most concerning, but many of the vulnerabilities that end up being exploited are rated as Important vs Critical.”

For example, Satnam Narang from Tenable notes that two remote code execution flaws in Microsoft Color Management (CVE-2020-1117) and Windows Media Foundation (CVE-2020-1126) could be exploited by tricking a user into opening a malicious email attachment or visiting a website that contains code designed to exploit the vulnerabilities. However, Microsoft rates these vulnerabilities as “Exploitation Less Likely,” according to their Exploitability Index.

In contrast, three elevation of privilege vulnerabilities that received a rating of “Exploitation More Likely” were also patched, Narang notes. These include a pair of “Important” flaws in Win32k (CVE-2020-1054, CVE-2020-1143) and one in the Windows Graphics Component (CVE-2020-1135). Elevation of Privilege vulnerabilities are used by attackers once they’ve managed to gain access to a system in order to execute code on their target systems with elevated privileges. There are at least 56 of these types of fixes in the May release.

Schell says if your organization’s plan for prioritizing the deployment of this month’s patches stops at vendor severity or even CVSS scores above a certain level you may want to reassess your metrics.

“Look to other risk metrics like Publicly Disclosed, Exploited (obviously), and Exploitability Assessment (Microsoft specific) to expand your prioritization process,” he advised.

Continue reading →


9
Jan 19

Patch Tuesday, January 2019 Edition

Microsoft on Tuesday released updates to fix roughly four dozen security issues with its Windows operating systems and related software. All things considered, this first Patch Tuesday of 2019 is fairly mild, bereft as it is of any new Adobe Flash updates or zero-day exploits. But there are a few spicy bits to keep in mind. Read on for the gory details. Continue reading →


19
Dec 18

Microsoft Issues Emergency Fix for IE Zero Day

Microsoft today released an emergency software patch to plug a critical security hole in its Internet Explorer (IE) Web browser that attackers are already using to break into Windows computers.

The software giant said it learned about the weakness (CVE-2018-8653) after receiving a report from Google about a new vulnerability being used in targeted attacks.

Satnam Narang, senior research engineer at Tenable, said the vulnerability affects the following installations of IE: Internet Explorer 11 from Windows 7 to Windows 10 as well as Windows Server 2012, 2016 and 2019; IE 9 on Windows Server 2008; and IE 10 on Windows Server 2012.

“As the flaw is being actively exploited in the wild, users are urged to update their systems as soon as possible to reduce the risk of compromise,” Narang said. Continue reading →