Use After Free in Exim
CVE-2026-45185
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 cl…
Vulnerability class: Use-After-Free
EPSS: 0.001 (24.1th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Exim — versions 4.97
- N/a — versions n/a
Weakness classification (CWE)
Public proof-of-concept exploits
References
- cve@mitre.org (Vendor Advisory)
- cve@mitre.org (Product)
- cve@mitre.org (Broken Link)
- cve@mitre.org (Release Notes)
- cve@mitre.org (Issue Tracking)
- cve@mitre.org (Mailing List, Third Party Advisory)
- cve@mitre.org (Third Party Advisory)
- af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Third Party Advisory)
Frequently asked questions
- What is CVE-2026-45185?
- CVE-2026-45185 is a critical-severity vulnerability in Exim, classified under Use After Free. CVSS score: 9.8/10. Published 2026-05-12.
- How severe is CVE-2026-45185?
- Critical severity. CVSS v3 base score is 9.8 out of 10.
- Is CVE-2026-45185 known to be exploited?
- 3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.