CVE-2021-34448
Published: November 3, 2021
Official Description
Microsoft Windows Scripting Engine contains an unspecified vulnerability that allows for memory corruption.
CISA KEV Advisory
Microsoft Windows Scripting Engine Memory Corruption Vulnerability
Microsoft Windows Scripting Engine contains an unspecified vulnerability that allows for memory corruption.
Apply updates per vendor instructions.
Risk Analysis
This unspecified vulnerability in Microsoft Windows Scripting Engine allows for memory corruption. Although a CVSS score is not available, its HIGH severity and confirmed exploitation in the wild by CISA indicate it is a critical threat. The low EPSS score of 0.02015 is superseded by the confirmed active exploitation.
This vulnerability is actively being exploited in the wild, as confirmed by its inclusion in CISA's KEV catalog. Memory corruption vulnerabilities can often be exploited remotely through crafted input.
Organizations should apply the latest security updates for Microsoft Windows to mitigate this vulnerability. Disabling or restricting the use of scripting engines where not essential can also reduce the attack surface.
Technical Analysis
CVE-2021-34448 requires local access, meaning attackers must already have a foothold on the target system.
Exploitation requires some privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
CISA has added CVE-2021-34448 to the Known Exploited Vulnerabilities (KEV) catalog, confirming active exploitation in the wild. U.S. federal agencies are required to patch this within the mandated timeframe, and all organizations should treat remediation as urgent.
Affected Vendors & Products
Exploit & PoC Resources
All References (1)
Quick Facts
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2021-34448 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
- !CISA KEV: Federal agencies must patch per BOD 22-01 timeline
- !Active exploitation confirmed — treat as P1