CVE-2026-6722

Description

In PHP versions 8.2.* before 8.2.31, 8.3.* before 8.3.31, 8.4.* before 8.4.21, and 8.5.* before 8.5.6, the SOAP extension's object deduplication mechanism stores pointers to PHP objects in a global map without incrementing their reference counts. When an apache:Map node contains duplicate keys, processing the second entry overwrites the first in the temporary result map, freeing the original PHP object while its stale pointer remains in the map. A subsequent href reference to the freed node can copy the dangling pointer into the result. As PHP string allocations can reclaim the freed memory region, an attacker with control over the SOAP request body can exploit this use-after-free to achieve remote code execution.

How to fix CVE-2026-6722

To remediate CVE-2026-6722, upgrade the affected package to a fixed version below.

• —upgrade to 8.2.31 or later
• —upgrade to 8.2.31 or later
• —upgrade to 8.2.31 or later
• —upgrade to 7.4.33-1+deb11u11 or later
• —upgrade to 8.2.31-1~deb12u1 or later
• —upgrade to 8.4.21-1~deb13u1 or later

Is CVE-2026-6722 being exploited?

Low — EPSS is 0.4%, meaning exploitation activity has not been observed at scale.

Affected packages (6)

• >= 8.2.0, < 8.2.31, >= 8.3.0, < 8.3.31, >= 8.4.0, < 8.4.21, >= 8.5.0, < 8.5.6
• >= 8.2.0, < 8.2.31, >= 8.3.0, < 8.3.31, >= 8.4.0, < 8.4.21, >= 8.5.0, < 8.5.6
• >= 8.2.0, < 8.2.31, >= 8.3.0, < 8.3.31, >= 8.4.0, < 8.4.21, >= 8.5.0, < 8.5.6
• from 0, < 7.4.33-1+deb11u11
• from 0, < 8.2.31-1~deb12u1
• from 0, < 8.4.21-1~deb13u1

CVSS scores

References (3)

• ADVISORYsecurity-tracker.debian.org/tracker/CVE-2026-6722
• WEBgithub.com/php/php-src/security/advisories/GHSA-85c2-q967-79q5
• WEBnvd.nist.gov/vuln/detail/CVE-2026-6722