CVE-2025-6491 Affecting php:8.3/php-dbg package, versions <0:8.3.26-1.module_el9.7.0+197+324afee8


Severity

Recommended
medium

Based on AlmaLinux security rating.

Threat Intelligence

EPSS
0.99% (60th percentile)

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  • Snyk IDSNYK-ALMALINUX9-PHP-14552011
  • published23 Dec 2025
  • disclosed27 Jan 2026

Introduced: 23 Dec 2025

CVE-2025-6491  (opens in a new tab)

How to fix?

Upgrade AlmaLinux:9 php:8.3/php-dbg to version 0:8.3.26-1.module_el9.7.0+197+324afee8 or higher.
This issue was patched in ALSA-2025:23309.

NVD Description

Note: Versions mentioned in the description apply only to the upstream php:8.3/php-dbg package and not the php:8.3/php-dbg package as distributed by AlmaLinux. See How to fix? for AlmaLinux:9 relevant fixed versions and status.

In PHP versions:8.1.* before 8.1.33, 8.2.* before 8.2.29, 8.3.* before 8.3.23, 8.4.* before 8.4.10 when parsing XML data in SOAP extensions, overly large (>2Gb) XML namespace prefix may lead to null pointer dereference. This may lead to crashes and affect the availability of the target server.

CVSS Base Scores

version 3.1