Rapid7

vulnerability

PHP Vulnerability: CVE-2025-6491

Severity
7
CVSS
(AV:N/AC:M/Au:N/C:N/I:N/A:C)
Published
Feb 17, 2026
Added
Feb 17, 2026
Modified
Mar 30, 2026

Description

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.

Solutions

php-upgrade-8_1_33php-upgrade-8_2_29php-upgrade-8_3_23php-upgrade-8_4_10
Title
Rapid7 Labs

2026 Global Threat Landscape Report

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