Vulnerability · Published May 10, 2026 · Assigned by php

CVE-2026-7263DoS attack via DOMNode::C14N()

High 7.5

In plain English

A high-severity infinite loop in PHP from PHP Group. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 29% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.4%top 70.8% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

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.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
AlmaLinux:10php8.48.4.21-1.el10_2ALSA-2026:22649
AlmaLinux:10php8.4-bcmath8.4.21-1.el10_2ALSA-2026:22649
AlmaLinux:10php8.4-cli8.4.21-1.el10_2ALSA-2026:22649
AlmaLinux:10php8.4-common8.4.21-1.el10_2ALSA-2026:22649
AlmaLinux:10php8.4-dba8.4.21-1.el10_2ALSA-2026:22649
AlmaLinux:10php8.4-dbg8.4.21-1.el10_2ALSA-2026:22649
AlmaLinux:10php8.4-devel8.4.21-1.el10_2ALSA-2026:22649
AlmaLinux:10php8.4-embedded8.4.21-1.el10_2ALSA-2026:22649
AlmaLinux:10php8.4-enchant8.4.21-1.el10_2ALSA-2026:22649
AlmaLinux:10php8.4-ffi8.4.21-1.el10_2ALSA-2026:22649
AlmaLinux:10php8.4-fpm8.4.21-1.el10_2ALSA-2026:22649
AlmaLinux:10php8.4-gd8.4.21-1.el10_2ALSA-2026:22649
AlmaLinux:10php8.4-gmp8.4.21-1.el10_2ALSA-2026:22649
AlmaLinux:10php8.4-intl8.4.21-1.el10_2ALSA-2026:22649
AlmaLinux:10php8.4-ldap8.4.21-1.el10_2ALSA-2026:22649
AlmaLinux:10php8.4-mbstring8.4.21-1.el10_2ALSA-2026:22649
AlmaLinux:10php8.4-mysqlnd8.4.21-1.el10_2ALSA-2026:22649
AlmaLinux:10php8.4-odbc8.4.21-1.el10_2ALSA-2026:22649
AlmaLinux:10php8.4-opcache8.4.21-1.el10_2ALSA-2026:22649
AlmaLinux:10php8.4-pdo8.4.21-1.el10_2ALSA-2026:22649
AlmaLinux:10php8.4-pgsql8.4.21-1.el10_2ALSA-2026:22649
AlmaLinux:10php8.4-process8.4.21-1.el10_2ALSA-2026:22649
AlmaLinux:10php8.4-snmp8.4.21-1.el10_2ALSA-2026:22649
AlmaLinux:10php8.4-soap8.4.21-1.el10_2ALSA-2026:22649
AlmaLinux:10php8.4-xml8.4.21-1.el10_2ALSA-2026:22649
Alpine:v3.22php848.4.27-r0ALPINE-CVE-2026-7263
Alpine:v3.23php848.4.21-r0ALPINE-CVE-2026-7263
Alpine:v3.23php858.5.6-r0ALPINE-CVE-2026-7263
Alpine:v3.24php858.5.6-r0ALPINE-CVE-2026-7263
Debian:13php8.48.4.21-1~deb13u1DEBIAN-CVE-2026-7263
Debian:14php8.48.4.21-1DEBIAN-CVE-2026-7263
Rocky Linux:10php8.40:8.4.21-1.el10_2RLSA-2026:22649
Ubuntu:26.04:LTSphp8.58.5.4-0ubuntu1.1UBUNTU-CVE-2026-7263

Affected products (as reported)

VendorProductVersions
PHP Group PHP 8.4.* – before 8.4.218.5.* – before 8.5.6

Weakness: CWE-404, CWE-835 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References