Security Experts:

Connect with us

Hi, what are you looking for?

SecurityWeekSecurityWeek

Malware & Threats

Microsoft Patches Another Internet Explorer Flaw Exploited in Attacks

Microsoft’s Patch Tuesday updates for November 2019 fix over 70 vulnerabilities, including an Internet Explorer flaw that has been exploited in attacks.

Microsoft’s Patch Tuesday updates for November 2019 fix over 70 vulnerabilities, including an Internet Explorer flaw that has been exploited in attacks.

The zero-day vulnerability, tracked as CVE-2019-1429, affects the scripting engine used by Internet Explorer 9, 10 and 11. Microsoft describes the security hole as a memory corruption bug that can allow an attacker to execute arbitrary code in the context of the current user by convincing the target to visit a specially crafted website with Internet Explorer or open a malicious Office document.

Microsoft has credited an anonymous researcher working with iDefense Labs, Ivan Fratric of Google Project Zero, Clément Lecigne of Google’s Threat Analysis Group, and Resecurity for reporting the vulnerability.

Google’s Threat Analysis Group has informed Microsoft of several actively exploited Windows and Internet Explorer vulnerabilities in the past year, but information about the attacks is rarely made public. In many cases, however, these flaws were likely exploited in targeted attacks rather than mass exploitation campaigns.

On the other hand, Trend Micro’s Zero Day Initiative (ZDI) has pointed out that other threat groups could also start exploiting CVE-2019-1429 now that they have access to the patch.

ZDI also notes that since the vulnerability can be exploited via malicious Office documents, even users who don’t utilize Internet Explorer are vulnerable to attacks — Microsoft says the attack works if the document hosts the Internet Explorer rendering engine.

SecurityWeek has reached out to both Resecurity and Google to see if they can share any information on the attacks currently exploiting CVE-2019-1429.

A dozen other critical vulnerabilities that allow remote code execution have been patched this month by Microsoft, including ones affecting Exchange, Windows, Internet Explorer, and Hyper-V.

“Looking through the Critical-rated patches, the updates for Hyper-V stand out the most. Five separate code execution bugs receive patches this month, and each could allow a user on the guest OS to execute code on the underlying host OS,” ZDI said in a blog post.

UPDATE. In a blog post published on Tuesday, Resecurity revealed that CVE-2019-1429 and a previously reported vulnerability, tracked as CVE-2019-0880, are likely exploited by the same threat group.

“We assume both identified 0-day vulnerabilities are related to the tradecraft of the same cyberespionage group focused on APT campaigns against defense, federal and financial sector. The geography of their end targets (victims) is extremely broad and include Middle East, APAC, USA and European Union. Previously, the group was leveraging possible ‘false flag’ attack – that’s why attribution at this moment is fuzzy. We continue to monitor the activity of the group and update our customers and intelligence community about the new previously unknown threats and zero-day vulnerabilities,” says Gene Yoo, CEO of Resecurity.

Related: Microsoft Patches Two Windows Flaws Exploited in Targeted Attacks

Related: Microsoft Patches Internet Explorer Zero-Day Reported by Google

Related: Microsoft Patches Internet Explorer Vulnerability Exploited in Attacks

Written By

Eduard Kovacs (@EduardKovacs) is a contributing editor at SecurityWeek. He worked as a high school IT teacher for two years before starting a career in journalism as Softpedia’s security news reporter. Eduard holds a bachelor’s degree in industrial informatics and a master’s degree in computer techniques applied in electrical engineering.

Click to comment

Daily Briefing Newsletter

Subscribe to the SecurityWeek Email Briefing to stay informed on the latest threats, trends, and technology, along with insightful columns from industry experts.

Join this webinar to learn best practices that organizations can use to improve both their resilience to new threats and their response times to incidents.

Register

Join this live webinar as we explore the potential security threats that can arise when third parties are granted access to a sensitive data or systems.

Register

Expert Insights

Related Content

Vulnerabilities

Less than a week after announcing that it would suspended service indefinitely due to a conflict with an (at the time) unnamed security researcher...

Cybercrime

The changing nature of what we still generally call ransomware will continue through 2023, driven by three primary conditions.

Cybercrime

No one combatting cybercrime knows everything, but everyone in the battle has some intelligence to contribute to the larger knowledge base.

Risk Management

The supply chain threat is directly linked to attack surface management, but the supply chain must be known and understood before it can be...

Cybercrime

A recently disclosed vBulletin vulnerability, which had a zero-day status for roughly two days last week, was exploited in a hacker attack targeting the...

Vulnerabilities

Apple has released updates for macOS, iOS and Safari and they all include a WebKit patch for a zero-day vulnerability tracked as CVE-2023-23529.

Vulnerabilities

Patch Tuesday: Microsoft warns vulnerability (CVE-2023-23397) could lead to exploitation before an email is viewed in the Preview Pane.

Application Security

Drupal released updates that resolve four vulnerabilities in Drupal core and three plugins.