CVE-2021-38646
Published: March 28, 2022
Official Description
Microsoft Office Access Connectivity Engine contains an unspecified vulnerability which can allow for remote code execution.
CISA KEV Advisory
Microsoft Office Access Connectivity Engine Remote Code Execution Vulnerability
Microsoft Office Access Connectivity Engine contains an unspecified vulnerability which can allow for remote code execution.
Apply updates per vendor instructions.
Risk Analysis
This high-severity unspecified vulnerability in Microsoft Office Access Connectivity Engine allows for remote code execution. The high EPSS score of 0.42730 indicates a significant likelihood of exploitation, and its presence in CISA's KEV catalog confirms it has been actively exploited.
This vulnerability is actively exploited in the wild, indicating a critical and immediate threat. It is remotely exploitable.
Ensure Microsoft Office and its components, including the Access Connectivity Engine, are fully updated. Exercise caution with untrusted files and sources.
Technical Analysis
CVE-2021-38646 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-2021-38646 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-2021-38646 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