Remotely triggerable out-of-bounds heap write in dhclient_CVE-2026-42512

7.3 / 10

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

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.

Basic Information

ID CVE-2026-42512

Source freebsd

Published Apr 30, 2026 at 07:58

Modified Apr 30, 2026 at 13:09

Affected Product

Vendor FreeBSD

Product FreeBSD

Version 15.0-RELEASE

Affected Versions FreeBSD FreeBSD 15.0-RELEASE
FreeBSD FreeBSD 14.4-RELEASE
FreeBSD FreeBSD 14.3-RELEASE
FreeBSD FreeBSD 13.5-RELEASE

CWE Classification

CWE-122

References

security.freebsd.org /advisories/FreeBSD-SA-26:15.dhclient.asc

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    "published": "2026-04-30T07:58:37.145Z",
    "modified": "2026-04-30T13:09:57.171Z",
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