CVE-2026-45185
CVSS Score
9.8
EPSS Score
0.0%
EPSS Percentile
0th
Exim before 4.99.3, in certain GnuTLS configurations, has a remotely reachable use-after-free in the BDAT body parsing path. It is triggered when a client sends a TLS close_notify mid-body during a CHUNKING transfer, followed by a final cleartext byte on the same TCP connection. This can lead to heap corruption. An unauthenticated network attacker exploiting this vulnerability could execute arbitrary code.
| CWE | CWE-416 |
| Vendor | exim |
| Product | exim |
| Published | May 12, 2026 |
| Last Updated | May 13, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Affected Versions
Exim / Exim
4.97 < 4.99.3
References
exim.org: https://exim.org code.exim.org: https://code.exim.org/exim/wiki/wiki/EximSecurity exim.org: https://exim.org/static/doc/security/CVE-2026-45185.txt xbow.com: https://xbow.com/blog/dead-letter-cve-2026-45185-xbow-found-rce-exim news.ycombinator.com: https://news.ycombinator.com/item?id=48111748 openwall.com: https://www.openwall.com/lists/oss-security/2026/05/12/4 exim.org: https://exim.org/static/doc/security/EXIM-Security-2026-05-01.1/ openwall.com: http://www.openwall.com/lists/oss-security/2026/05/12/25