In PHP versions 8.4.* before 8.4.21 and 8.5.* before 8.5.6, DOMNode::C14N() method may process the XML data incorrectly, causing a circular linked list in the data structure representing the XML document. This may cause subsequent processing of the XML document to enter infinite loop, causing denial of service in the processing application.
https://github.com/php/php-src/security/advisories/GHSA-4jhr-8w89-j733
Published: 2026-05-10
Updated: 2026-05-12
Base Score: 7.8
Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C
Severity: High
Base Score: 7.5
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Severity: High
Base Score: 6.3
Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:L
Severity: Medium
EPSS: 0.00042