PHP up to 8.2.30/8.3.30/8.4.20/8.5.5 cross site scripting

Summaryinfo

A vulnerability marked as problematic has been reported in PHP up to 8.2.30/8.3.30/8.4.20/8.5.5. This affects an unknown part. This manipulation causes cross site scripting. This vulnerability is registered as CVE-2026-6735. Remote exploitation of the attack is possible. No exploit is available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic was found in PHP up to 8.2.30/8.3.30/8.4.20/8.5.5. Affected by this vulnerability is an unknown code. The manipulation with an unknown input leads to a cross site scripting vulnerability. The CWE definition for the vulnerability is CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. As an impact it is known to affect integrity. The summary by CVE is:

In PHP versions 8.2.* before 8.2.31, 8.3.* before 8.3.31, 8.4.* before 8.4.21, 8.5.* before 8.5.6, due to improper sanitation of user data, it allows an attacker to compose an URL, which will cause the target to execute arbitrary JavaScript code (XSS) on the target's machine when the target is viewing the PHP-FPM status page.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-6735 since 04/21/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 07/03/2026). MITRE ATT&CK project uses the attack technique T1059.007 for this issue.

The vulnerability scanner Nessus provides a plugin with the ID 313734 (Fedora 44 : php (2026-c66eaae759)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 8.2.31, 8.3.31, 8.4.21 or 8.5.6 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (313734) and CERT Bund (WID-SEC-2026-1433). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Fedora Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• RESF Rocky Linux
• Microsoft Azure Linux
• Open Source PHP
• Zend ZendPHP
• cPanel cPanel/WHM

Productinfo

Type

• Programming Language Software

Name

• PHP

Version

• 8.2.0
• 8.2.1
• 8.2.2
• 8.2.3
• 8.2.4
• 8.2.5
• 8.2.6
• 8.2.7
• 8.2.8
• 8.2.9
• 8.2.10
• 8.2.11
• 8.2.12
• 8.2.13
• 8.2.14
• 8.2.15
• 8.2.16
• 8.2.17
• 8.2.18
• 8.2.19
• 8.2.20
• 8.2.21
• 8.2.22
• 8.2.23
• 8.2.24
• 8.2.25
• 8.2.26
• 8.2.27
• 8.2.28
• 8.2.29
• 8.2.30
• 8.3.0
• 8.3.1
• 8.3.2
• 8.3.3
• 8.3.4
• 8.3.5
• 8.3.6
• 8.3.7
• 8.3.8
• 8.3.9
• 8.3.10
• 8.3.11
• 8.3.12
• 8.3.13
• 8.3.14
• 8.3.15
• 8.3.16
• 8.3.17
• 8.3.18
• 8.3.19
• 8.3.20
• 8.3.21
• 8.3.22
• 8.3.23
• 8.3.24
• 8.3.25
• 8.3.26
• 8.3.27
• 8.3.28
• 8.3.29
• 8.3.30
• 8.4.0
• 8.4.1
• 8.4.2
• 8.4.3
• 8.4.4
• 8.4.5
• 8.4.6
• 8.4.7
• 8.4.8
• 8.4.9
• 8.4.10
• 8.4.11
• 8.4.12
• 8.4.13
• 8.4.14
• 8.4.15
• 8.4.16
• 8.4.17
• 8.4.18
• 8.4.19
• 8.4.20
• 8.5.0
• 8.5.1
• 8.5.2
• 8.5.3
• 8.5.4
• 8.5.5

License

• open-source

Website

• Product: https://www.php.org/

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Discussion