CVE-2026-91767NVD

Vulnerability Summary

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.

Severity Level

MEDIUM(6.5)

Published Date

Sep 25, 2026

Last Modified

Sep 25, 2026

Exploitation Status

No confirmed exploitation yet

CVE Record Status

Published

EPSS Score (30-Day)

Data Pending

Root Weakness (CWE)

CWE-122: Unknown/Unlisted Weakness ↗

Refer to the official MITRE database for detailed architectural specifications regarding this weakness.

CVSS v3.1 Base Metrics — Score 6.5 (MEDIUM)

Attack VectorAdjacent

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

ConfidentialityHigh

IntegrityNone

AvailabilityNone

Affected & Patched Versions

Affected Versions

Not provided by NVD for this CVE.

Patched Versions

Not provided by NVD for this CVE.

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