CVE-2026-91767

Heap-buffer-overflow in php_openssl_matches_wildcard_name on crafted server cert wildcard CN

Published: Sep 25, 2026Updated: Sep 25, 2026 Sources: CVE List NVDCWE-122

6.5MEDIUM

Description

php_openssl_matches_wildcard_name() in ext/openssl/xp_ssl.c underflows the length argument passed to memchr() when a TLS server certificate presents a wildcard name whose literal characters are together longer than the hostname being verified. A malicious server presenting such a certificate makes the PHP client read up to SIZE_MAX bytes past the end of a heap allocation. The path is reachable from any default client stream, because verify_peer_name is enabled by default.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:AAttack Vector

Adjacent

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:HConfidentiality

High

I:NIntegrity

None

A:NAvailability

None

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Weaknesses

CWE-122

Affected Products

PHP Group

oss-projectaka php, pear

PHPLibraryLibrary

OSS Libraries

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Privilege Escalation

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References

https://github.com/php/php-src/security/advisories/GHSA-xr7j-rvgx-xq5p

github.com

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