CVE-2025-6491

🔶 medium

Summary

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 Score

5.9

Medium

EPSS Score

0.1

Exploit Probability

Published Date

2025-07-13

First Seen: 2026-01-05

📊 Relative Risk Intelligence

This CVE is Lower Risk - more severe than 33.3% of all 329,456 vulnerabilities in our database.

#219,613

Below average severity

Severity Percentile

🎯 CISA SSVC Assessment Updated: Jul 14, 2025

🔍 Exploitation Status

Poc

Proof-of-concept available

⚙️ Automatable

Requires human interaction

💥 Technical Impact

Partial

Limited system impact

🏆 Discovered By

Ahmed Lekssays (reporter)

SSVC data provided by CISA

Last Modified 2025-11-04

Source NVD 🔗

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

CWE IDs (Weakness Types)

CWE-476

📦 Affected Products 4

Vendor	Product	Status	Affected Versions
php	php	Affected	≥ 8.1.0 < 8.1.33
php	php	Affected	≥ 8.2.0 < 8.2.29
php	php	Affected	≥ 8.3.0 < 8.3.23
php	php	Affected	≥ 8.4.0 < 8.4.10

🔗 References 3

https://github.com/php/php-src/security/advisories/G...

Exploit Vendor Advisory

http://www.openwall.com/lists/oss-security/2025/07/11/4

https://lists.debian.org/debian-lts-announce/2025/07...

🔗 Related CVEs 6

CVE ID	Severity	CVSS	EPSS	Summary	Published
CVE-2025-14177	⚠️ high	7.5	0.0	In PHP versions:8.1.* before 8.1.34, 8.2.* before 8.2.30, 8.3.* before 8.3.29, 8.4.* before 8.4.16, 8.5.* before 8.5.1, ...	2025-12-27
CVE-2025-14178	🔶 medium	6.5	0.1	In PHP versions:8.1.* before 8.1.34, 8.2.* before 8.2.30, 8.3.* before 8.3.29, 8.4.* before 8.4.16, 8.5.* before 8.5.1, ...	2025-12-27
CVE-2025-14180	⚠️ high	7.5	0.0	In PHP versions 8.1.* before 8.1.34, 8.2.* before 8.2.30, 8.3.* before 8.3.29, 8.4.* before 8.4.16, 8.5.* before 8.5.1 w...	2025-12-27
CVE-2025-1220	ℹ️ low	3.7	0.0	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 some functions like f...	2025-07-13
CVE-2025-1735	🔶 medium	5.9	0.1	In PHP versions:8.1.* before 8.1.33, 8.2.* before 8.2.29, 8.3.* before 8.3.23, 8.4.* pgsql and pdo_pgsql escaping functi...	2025-07-13
CVE-2024-11235	⚠️ high	8.1	1.5	In PHP versions 8.3.* before 8.3.19 and 8.4.* before 8.4.5, a code sequence involving __set handler or ??= operator a...	2025-04-04

These CVEs affect the same products