CVE-2010-4344
KEVExim Heap-Based Buffer Overflow Vulnerability
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.
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 that includes two MAIL commands in conjunction with a large message containing crafted headers, leading to improper rejection logging.
CVSS 3.1 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HPublishedDec 14, 2010
Last modifiedJun 16, 2026
Added to KEVMar 25, 2022
Remediation dueApr 15, 2022
References
- atmail.com/blog/2010/atmail-6204-now-available/Broken Link
- bugs.exim.org/show_bug.cgi?id=787Issue TrackingPatch
- git.exim.org/exim.git/commit/24c929a27415c7cfc7126c47e4cad39acf3efa6bMailing ListPatch
- lists.exim.org/lurker/message/20101210.164935.385e04d0.en.htmlMailing ListPatch
- lists.opensuse.org/opensuse-security-announce/2010-12/msg00003.htmlMailing ListThird Party Advisory
- openwall.com/lists/oss-security/2010/12/10/1Mailing ListThird Party Advisory
- secunia.com/advisories/40019Broken LinkVendor Advisory
- secunia.com/advisories/42576Broken LinkVendor Advisory
- secunia.com/advisories/42586Broken LinkVendor Advisory
- secunia.com/advisories/42587Broken LinkVendor Advisory
- secunia.com/advisories/42589Broken LinkVendor Advisory
- cpanel.net/2010/12/exim-remote-memory-corruption-vulnerability-notification-cve-2010-4344.htmlBroken Link
0 recent articles mention this CVE
86
Risk assessment · Critical
Actively exploited. Patch immediately.
- Exploitation
- Confirmed in the wild (CISA KEV)
- Federal remediation deadline
- Overdue by 1656 days
- CVSS
- 9.8 CRITICAL
- EPSS (30-day exploit probability)
- 71.7% · top 1% of all CVEs
- Weakness
- CWE-787
- Attack vector
- Network, remotely reachable
- Preconditions
- No privileges and no user interaction
Recommended actions
- 1.Apply updates per vendor instructions.
- 2.Treat as emergency change: patch or isolate internet-facing instances first.
- 3.Review exposure: confirm which instances are reachable from the internet and restrict access until patched.
- 4.Hunt for compromise: review logs for the disclosure window, not just from the patch date.
Assessment is derived automatically from the live signals above; verify against your own asset inventory.