Linux Distros Unpatched Vulnerability : CVE-2026-12087

critical Nessus Plugin ID 321157

Synopsis

The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be patched.

Description

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

- Socket versions before 2.041 for Perl have an out-of-bounds heap read. In Socket.xs, pack_ip_mreq_source() checks the length of its source argument before the argument is read, so the check tests the byte length carried over from the preceding multiaddr argument instead. Both addresses occupy a 4-byte field, so a valid multiaddr lets a source of any length pass the check, and the source is then copied into the 4-byte imr_sourceaddr field with a fixed-size copy. A source shorter than 4 bytes is not rejected, and the copy reads up to 3 bytes past the end of its buffer. Calling pack_ip_mreq_source() with a source value shorter than 4 bytes copies adjacent heap memory into the returned packed structure. (CVE-2026-12087)

Note that Nessus relies on the presence of the package as reported by the vendor.

Solution

There is no known solution at this time.

See Also

https://security-tracker.debian.org/tracker/CVE-2026-12087

Plugin Details

Severity: Critical

ID: 321157

File Name: unpatched_CVE_2026_12087.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Misc.

Published: 6/16/2026

Updated: 6/16/2026

Supported Sensors: Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.4

CVSS v2

Risk Factor: Medium

Base Score: 5.5

Temporal Score: 4.7

Vector: CVSS2#AV:N/AC:L/Au:S/C:P/I:N/A:P

CVSS Score Source: CVE-2026-12087

CVSS v3

Risk Factor: Critical

Base Score: 9.1

Temporal Score: 8.3

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Temporal Vector: CVSS:3.0/E:U/RL:U/RC:C

Vulnerability Information

CPE: cpe:/o:debian:debian_linux:14.0, cpe:/o:debian:debian_linux:11.0, p-cpe:/a:debian:debian_linux:libsocket-perl, cpe:/o:debian:debian_linux:13.0, p-cpe:/a:debian:debian_linux:perl, cpe:/o:debian:debian_linux:12.0

Required KB Items: Host/local_checks_enabled, Host/cpu, global_settings/vendor_unpatched, Host/OS/identifier

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 6/15/2026

Reference Information

CVE: CVE-2026-12087