AlmaLinux 9.6 [TuxCare] Security Update: cups / cups-client / cups-devel / cups-filesystem / cups-ipptool / etc Multiple Vulnerabilities (ALMALINUX9.6:CLSA-2026:1776768072)

medium Nessus Plugin ID 351637

Synopsis

The AlmaLinux host is missing one or more security updates.

Description

The AlmaLinux 9.6 host has packages installed that are affected by multiple vulnerabilities as referenced in the TuxCare ALMALINUX9.6:CLSA-2026:1776768072 advisory.

- OpenPrinting CUPS is an open source printing system for Linux and other Unix-like operating systems. In versions 2.4.16 and prior, in a network-exposed cupsd with a shared target queue, an unauthorized client can send a Print-Job to that shared PostScript queue without authentication. The server accepts a page- border value supplied as textWithoutLanguage, preserves an embedded newline through option escaping and reparse, and then reparses the resulting second-line PPD: text as a trusted scheduler control record. A follow-up raw print job can therefore make the server execute an attacker-chosen existing binary such as /usr/bin/vim as lp. At time of publication, there are no publicly available patches. (CVE-2026-34980)

- OpenPrinting CUPS is an open source printing system for Linux and other Unix-like operating systems. In versions 2.4.16 and prior, an integer underflow vulnerability in _ppdCreateFromIPP() (cups/ppd-cache.c) allows any unprivileged local user to crash the cupsd root process by supplying a negative job-password- supported IPP attribute. The bounds check only caps the upper bound, so a negative value passes validation, is cast to size_t (wrapping to ~2^64), and is used as the length argument to memset() on a 33-byte stack buffer. This causes an immediate SIGSEGV in the cupsd root process. Combined with systemd's Restart=on-failure, an attacker can repeat the crash for sustained denial of service. (CVE-2026-39314)

- OpenPrinting CUPS is an open source printing system for Linux and other Unix-like operating systems. In versions 2.4.16 and prior, a use-after-free vulnerability exists in the CUPS scheduler (cupsd) when temporary printers are automatically deleted. cupsdDeleteTemporaryPrinters() in scheduler/printers.c calls cupsdDeletePrinter() without first expiring subscriptions that reference the printer, leaving cupsd_subscription_t.dest as a dangling pointer to freed heap memory. The dangling pointer is subsequently dereferenced at multiple code sites, causing a crash (denial of service) of the cupsd daemon. With heap grooming, this can be leveraged for code execution. (CVE-2026-39316)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

Update the affected packages based on the guidance in TuxCare advisory ALMALINUX9.6:CLSA-2026:1776768072.

Plugin Details

Severity: Medium

ID: 351637

File Name: tuxcare_alma_linux_9.6_CLSA-2026-1776768072.nasl

Version: 1.1

Type: Local

Family: Alma Linux Local Security Checks

Published: 9/30/2026

Updated: 9/30/2026

Supported Sensors: Nessus Agent, Continuous Assessment, Nessus

Risk Information

VPR

Risk Factor: High

Score: 7.7

Percentile: 98.93

Vendor

Vendor Severity: Important

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5.6

Vector: CVSS2#AV:A/AC:H/Au:N/C:C/I:C/A:C

CVSS Score Source: CVE-2026-34980

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 7

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

Temporal Vector: CVSS:3.0/E:F/RL:O/RC:C

CVSS v4

Risk Factor: Medium

Base Score: 6.1

Threat Score: 5.6

Threat Vector: CVSS:4.0/E:P

Vector: CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:L/SC:N/SI:N/SA:N

Vulnerability Information

Required KB Items: Host/local_checks_enabled, Host/cpu, Host/AlmaLinux/release, Host/AlmaLinux/rpm-list, Host/OS/extended-third-party

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 4/21/2026

Vulnerability Publication Date: 4/3/2026

Reference Information

CVE: CVE-2026-34980, CVE-2026-39314, CVE-2026-39316

CLSA: 2026:1776768072

Detections

Analytics