CVE-2026-45185CWE-416

Exim before 4.99.3, in certain GnuTLS configurations, has a remotely reachable use-after-free in the BDAT body parsing path

Critical · published May 12, 2026

CVSS v3.1
9.8
EPSS
1%
Percentile
60.7
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
9.8 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00944 · 60.7th percentile
Weakness
CWE-416 · Use After Free
Published
2026-05-12T00:00Z
EPSS history
Timeline
  • 12 MAY 00:00Z
    Exim before 4.99.3, in certain GnuTLS configurations, has a remotely reachable use-after-free in the BDAT body parsing path
    cvelistv5