Microsoft on Monday released patches for two vulnerabilities, including an Internet Explorer zero-day and a denial-of-service (DoS) flaw affecting Microsoft Defender.
The Internet Explorer zero-day, tracked as CVE-2019-1367, has been described as a memory corruption issue that allows remote code execution. The security hole affects Internet Explorer 9, 10 and 11, and Microsoft says it’s aware of exploitation attempts against both newer and older versions.
“The vulnerability could corrupt memory in such a way that an attacker could execute arbitrary code in the context of the current user. An attacker who successfully exploited the vulnerability could gain the same user rights as the current user. If the current user is logged on with administrative user rights, an attacker who successfully exploited the vulnerability could take control of an affected system,” Microsoft said in an advisory.
In order to exploit this vulnerability, an attacker needs to convince the targeted user to visit a malicious website using a vulnerable version of Internet Explorer.
Microsoft has credited Clément Lecigne of Google’s Threat Analysis Group for reporting CVE-2019-1367. Google’s Threat Analysis Group informed Microsoft of several actively exploited Windows and Internet Explorer vulnerabilities in the past, including CVE-2019-0676, CVE-2019-0808 and CVE-2018-8653.
No details have been made available about the attacks exploiting CVE-2019-1367.
Microsoft has pointed out that, by default, Internet Explorer runs in a restricted mode called Enhanced Security Configuration on all supported versions of Windows Server, which should mitigate the risk.
Users who cannot apply the patches for this vulnerability have been provided a workaround that involves restricting access to JScript.dll, but this method can impact the functionality of features and components that rely on JScript.dll.
The second security update released by Microsoft on Monday patches a DoS vulnerability in Microsoft Defender, an anti-malware tool shipped with Windows.
The vulnerability, tracked as CVE-2019-1255, allows an attacker who has access to the targeted system to “prevent legitimate accounts from executing legitimate system binaries.”
Microsoft Forefront Endpoint Protection 2010, Security Essentials, and System Center Endpoint Protection products are also affected. The tech giant patched the vulnerability with an update to its Microsoft Malware Protection Engine (version 1.1.16400.2). Most users are not required to take any action as Malware Protection Engine updates are delivered automatically by default.
The issue was reported to Microsoft by researchers from F-Secure and Tencent, and there is no evidence that it has been exploited in the wild.
Related: Google Discloses Actively Exploited Windows Vulnerability
Related: Buhtrap Group Used Windows Zero-Day in Government Attack
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.
More from Eduard Kovacs
- ChatGPT Data Breach Confirmed as Security Firm Warns of Vulnerable Component Exploitation
- Thousands Access Fake DDoS-for-Hire Websites Set Up by UK Police
- Intel Boasts Attack Surface Reduction With New 13th Gen Core vPro Platform
- Dole Says Employee Information Compromised in Ransomware Attack
- High-Severity Vulnerabilities Found in WellinTech Industrial Data Historian
- CISA Expands Cybersecurity Committee, Updates Baseline Security Goals
- Exploitation of 55 Zero-Day Vulnerabilities Came to Light in 2022: Mandiant
- Organizations Notified of Remotely Exploitable Vulnerabilities in Aveva HMI, SCADA Products
Latest News
- Microsoft Puts ChatGPT to Work on Automating Cybersecurity
- Video: How to Build Resilience Against Emerging Cyber Threats
- Nigerian BEC Scammer Sentenced to Prison in US
- China’s Nuclear Energy Sector Targeted in Cyberespionage Campaign
- SecurityScorecard Guarantees Accuracy of Its Security Ratings
- ChatGPT Data Breach Confirmed as Security Firm Warns of Vulnerable Component Exploitation
- 14 Million Records Stolen in Data Breach at Latitude Financial Services
- Webinar Today: Understanding Hidden Third-Party Identity Access Risks
