CVE-2026-42512

HIGH

Remotely triggerable out-of-bounds heap write in dhclient

Title source: cna
STIX 2.1

Description

As dhclient is building an environment to pass to dhclient-script, it may need to resize the array of string pointers. The code which expands the array incorrectly calculates its new size when requesting memory, resulting in a heap buffer overrun. A specially crafted packet can cause dhclient to overrun its buffer of environment entries. This can result in a crash, but it may be possible to leverage this bug to achieve remote code execution.

References (1)

Core 1
Core References

Scores

CVSS v3 8.1
EPSS 0.0142
EPSS Percentile 69.3%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact total

Details

CWE
CWE-122
Status published
Products (8)
freebsd/freebsd 13.5 (14 CPE variants)
freebsd/freebsd 14.3 (12 CPE variants)
freebsd/freebsd 14.4 (4 CPE variants)
freebsd/freebsd 15.0 (7 CPE variants)
FreeBSD/FreeBSD 13.5-RELEASE - p13
FreeBSD/FreeBSD 14.3-RELEASE - p12
FreeBSD/FreeBSD 14.4-RELEASE - p3
FreeBSD/FreeBSD 15.0-RELEASE - p7
Published Apr 30, 2026
Tracked Since Apr 30, 2026