CVE-2025-6491 MEDIUM

CVE-2025-6491: NULL Pointer Dereference in PHP SOAP Extension via Large XML Namespace Prefix

Vendor Php Group
Product PHP
Weakness CWE-476
Published July 13, 2025
Last update November 4, 2025
View on NVD All CVEs

CVSS base score

5.9/10
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Confidentiality None
Integrity None

CVSS vector

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

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

July 13, 2025 CVE published
November 4, 2025 Record updated