CVE-2010-4344
Published: March 25, 2022
Official Description
Heap-based buffer overflow in the string_vformat function in string.c in Exim before 4.70 allows remote attackers to execute arbitrary code via an SMTP session.
CISA KEV Advisory
Exim Heap-Based Buffer Overflow Vulnerability
Heap-based buffer overflow in the string_vformat function in string.c in Exim before 4.70 allows remote attackers to execute arbitrary code via an SMTP session.
Apply updates per vendor instructions.
Risk Analysis
A heap-based buffer overflow in the Exim mail transfer agent (before version 4.70) allows remote attackers to execute arbitrary code via an SMTP session. The high EPSS score of 0.61976 and its presence in the KEV catalog indicate a significant and confirmed risk of exploitation.
This vulnerability has been actively exploited in the wild. It is remotely exploitable via an SMTP session without authentication.
Administrators should upgrade Exim to version 4.70 or later to patch this buffer overflow vulnerability. Ensure that mail servers are kept up-to-date with the latest security releases.
Technical Analysis
CVE-2010-4344 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-2010-4344 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.
Exploit & PoC Resources
All References (1)
Quick Facts
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2010-4344 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