Incorrect Provision of Specified Functionality Affecting exim4 package, versions <4.96-15+deb12u9


Severity

Recommended
0.0
high
0
10

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Threat Intelligence

EPSS
0.36% (28th percentile)

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  • Snyk IDSNYK-ECHOLATEST-EXIM4-18234363
  • published23 Jul 2026
  • disclosed30 Apr 2026

Introduced: 30 Apr 2026

CVE-2026-40684  (opens in a new tab)
CWE-684  (opens in a new tab)

How to fix?

Upgrade Echo:latest exim4 to version 4.96-15+deb12u9 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream exim4 package and not the exim4 package as distributed by Echo. See How to fix? for Echo:latest relevant fixed versions and status.

In Exim before 4.99.2, on systems using musl libc (not glibc), an attacker can crash the connection instance when malformed DNS data is present in PTR records. This is caused by a dn_expand oddity in octal printing.

CVSS Base Scores

version 3.1