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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
NVD MITRE
5.9CVSSMEDIUM
EPSS Score
0.9%
Top 43.6%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

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.

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

phpphp
Dev Tool
OSS Libraries / generic-library
UbuntuCanonical Ltd.
On-premOS
Operating Systems / linux-distro
openSUSE TumbleweedNovell Inc.
On-premOS
Operating Systems / linux-distro
Debian GNU/LinuxСообщество свободного программного обеспечения
On-premOS
Operating Systems / linux-distro
РЕД ОСООО «Ред Софт»
On-premOS
Operating Systems / linux-distro
phposs-projectUSOSS Librariesaka php language, pecl, pear
canonical ltd.commercialGBOperating Systemsaka canonical
novell inc.commercialUSOperating Systems
сообщество свободного программного обеспеченияoss-projectOperating Systemsaka сообщество свободного программного обеспечения, fsf
ооо «ред софт»commercialRUOperating Systemsaka red soft
and 12 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

Official Patch Available

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 →

Timeline

Published
Jul 13, 2025
Last Updated
Nov 4, 2025

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