CVE-2009-0557
Published: June 8, 2022
Official Description
Microsoft Office contains an object record corruption vulnerability that allows remote attackers to execute code via a crafted Excel file with a malformed record object.
CISA KEV Advisory
Microsoft Office Object Record Corruption Vulnerability
Microsoft Office contains an object record corruption vulnerability that allows remote attackers to execute code via a crafted Excel file with a malformed record object.
Apply updates per vendor instructions.
Risk Analysis
A vulnerability in Microsoft Office, specifically with Excel files, allows remote attackers to execute code through a malformed record object. The high EPSS score of 0.86365 indicates a very high probability of exploitation, making this a significant risk.
This vulnerability is actively exploited in the wild and is included in CISA's KEV catalog, confirming its use by malicious actors.
Ensure all Microsoft Office installations are fully updated with the latest security patches. Exercise caution when opening untrusted Excel files.
Technical Analysis
CVE-2009-0557 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-2009-0557 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-2009-0557 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