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CVE-2025-6491

NULL Pointer Dereference in PHP SOAP Extension via Large XML Namespace Prefix

Published: Jul 13, 2025Updated: Nov 4, 2025 Sources: CVE List NVD BDUCWE-476
5.9MEDIUM
NVD MITRE
EPSS Score
0.9%
Top 42.3%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:HPR:NUI:NS:UC:NI:NA:H
Exploitability
AV:NAttack Vector
Network
AC:HAttack Complexity
High
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High
Open in CVSS calculator →

Weaknesses

CWE-476

Affected Products

Novell Inc.
commercial·US
openSUSE TumbleweedOn-prem
Operating Systems / linux-distro
SUSE Linux Enterprise Server for SAP ApplicationsOn-premOS
Operating Systems / linux-distro
SUSE Manager ServerOn-prem
Operating Systems / linux-distro
SUSE Linux Enterprise High Performance ComputingOn-prem
Operating Systems / linux-distro
SUSE Linux Enterprise Module for Package HubOn-prem
Operating Systems / linux-distro
OpenSUSE LeapOn-premOS
Operating Systems / linux-distro
SUSE Linux Enterprise Module for Web ScriptingOn-prem
Operating Systems / linux-distro
SUSE Linux Enterprise Module for LegacyOn-prem
Operating Systems / linux-distro
Сообщество свободного программного обеспечения
oss-projectaka fsf
Debian GNU/LinuxOn-premOS
Operating Systems / linux-distro
libxml2LibraryLibrary
OSS Libraries / generic-library
PHP Group
oss-projectaka php, pear
PHPLibraryLibrary
OSS Libraries
php
oss-project·USaka pecl, php language, pear
phpDev Tool
OSS Libraries / generic-library
Canonical Ltd.
commercial·GBaka canonical
UbuntuOn-premOS
Operating Systems / linux-distro
ООО «Ред Софт»
commercial·RUaka red soft
РЕД ОСOn-premOS
Operating Systems / linux-distro
and 3 more affected products View all →

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques
Impact
Initial Access
View detailed technique mapping

References

https://github.com/php/php-src/security/advisories/GHSA-453j-q27h-5p8x
github.com
http://www.openwall.com/lists/oss-security/2025/07/11/4
openwall.com
https://lists.debian.org/debian-lts-announce/2025/07/msg00017.html
lists.debian.org
and 10 more references View all →

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