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.

Affected products

Exim, Gnutls, Linuxmint, Red Os, Ubuntu

Exim

< 4.99.3

Fix

Available

CVSS 3.1

9.8 CRITICAL

EPSS

1.2% (66th percentile)

Weakness

CWE-416

NVD status

Analyzed

Published

2026-05-12