CVE-2025-6491

5.9 mediumEPSS 1.1%

Medium (5.9) in php php. EPSS 1.1% chance of exploitation in the next 30 days.

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.

Severity

CVSS 3.1

5.9 medium

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

EPSS: 1.1% chance of exploitation in the next 30 days; higher than 66% of CVEs (scores of 2026-10-31)
CWE: CWE-476
Published: 2025-07-13
Modified: 2026-06-17
Record from: the NVD, synced 2026-10-19

Affected

php:php

References

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

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