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 cleartext byte on the same TCP connection. This can lead to heap corruption. An unauthenticated network attacker exploiting this vulnerability could execute arbitrary code.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://code.exim.org/exim/wiki/wiki/EximSecurity	Vendor Advisory
https://exim.org	Product
https://exim.org/static/doc/security/CVE-2026-45185.txt	Broken Link
https://exim.org/static/doc/security/EXIM-Security-2026-05-01.1/	Release Notes
https://news.ycombinator.com/item?id=48111748	Issue Tracking
https://www.openwall.com/lists/oss-security/2026/05/12/4	Mailing List Third Party Advisory
https://xbow.com/blog/dead-letter-cve-2026-45185-xbow-found-rce-exim	Third Party Advisory
http://www.openwall.com/lists/oss-security/2026/05/12/25	Mailing List Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:exim:exim:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-05-12 20:16

Updated : 2026-06-17 10:51

NVD link : CVE-2026-45185

Mitre link : CVE-2026-45185

CVE.ORG link : CVE-2026-45185

JSON object : View

Products Affected

exim

exim

CWE

CWE-416

Use After Free

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