Description
Exim before 4.99.1, with certain non-default rate-limit configurations, allows a remote heap-based buffer overflow because database records are cast directly to internal structures without validation.
Affected products
exim: exim
References5
- exim.org/static/doc/security/ Vendor Advisory
- exim.org/static/doc/security/EXIM-Security-2025-12-09.1/report.… Vendor Advisory
- www.openwall.com/lists/oss-security/2025/12/11/2 Mailing List
- www.openwall.com/lists/oss-security/2025/12/14/1 Mailing List
- www.openwall.com/lists/oss-security/2025/12/18/3 Mailing List
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 41 · as of 11 November 2026
- CWE
- CWE-122
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