CVE-2026-91767

mediumpriority · track · 26EPSS 0.001 · 1 %ileDEUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.11% (1st) EPSS

CVSS 6.5 · medium

Is it mine?

28 products

Check your exposure

Who says so?

3 sources

osv · cert_bund · nvd

EPSS · scored 2026-10-28

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.

cvss

Technical severity, 0–10. One row per scoring source.

6.5

010

base score 0–10 · higher = more severe · hover a vector to decode

v3.16.5mediumCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 3.6

v3.16.5mediumCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nsecondary · security@php.netexploitability 2.8 · impact 3.6

v3.16mediumCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-122US

affected products (28)

Products and version ranges known to be affected.

Amazon Linux 2all versionscert_bundDEcpe:/o:amazon:linux_2:-
Debian Linuxall versionscert_bundDEcpe:/o:debian:debian_linux:-
Oracle Linuxall versionscert_bundDEcpe:/o:oracle:linux:-
RESF Rocky Linuxall versionscert_bundDEcpe:/o:resf:rocky_linux:-
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
SUSE Linuxall versionscert_bundDEcpe:/o:suse:suse_linux:-
SUSE openSUSEall versionscert_bundDEcpe:/o:suse:opensuse:-
Zend ZendPHPall versionscert_bundDEcpe:/a:zend:zendphp:-
Open Source PHP< 8.2.34cert_bundDE
Open Source PHP< 8.3.35cert_bundDE
Open Source PHP< 8.4.26cert_bundDE
Open Source PHP< 8.5.11cert_bundDE
php php8.2.0 → 8.2.34nvdUScpe:2.3:a:php:php:*:*:*:*:*:*:*:*
php php8.3.0 → 8.3.35nvdUScpe:2.3:a:php:php:*:*:*:*:*:*:*:*
php php8.4.0 → 8.4.26nvdUScpe:2.3:a:php:php:*:*:*:*:*:*:*:*
php php8.5.0 → 8.5.11nvdUScpe:2.3:a:php:php:*:*:*:*:*:*:*:*
Bitnami libphp8.2.0 → 8.2.34osvUSpkg:bitnami/libphp
Bitnami libphp8.3.0 → 8.3.35osvUSpkg:bitnami/libphp
Bitnami libphp8.4.0 → 8.4.26osvUSpkg:bitnami/libphp
Bitnami libphp8.5.0 → 8.5.11osvUSpkg:bitnami/libphp

showing 20 of 28

advisories (4)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2026-3585PHP: Mehrere SchwachstellenDeutsch2026-09-24csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in PHP ausnutzen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen oder die Integrität zu verletzen.
BIT-libphp-2026-91767Heap-buffer-overflow in php_openssl_matches_wildcard_name on crafted server cert wildcard CN2026-10-01vendor · osvUS
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.
BIT-php-2026-91767Heap-buffer-overflow in php_openssl_matches_wildcard_name on crafted server cert wildcard CN2026-10-01vendor · osvUS
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.
BIT-php-min-2026-91767Heap-buffer-overflow in php_openssl_matches_wildcard_name on crafted server cert wildcard CN2026-10-01vendor · osvUS
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.

also known as (3)

Other names and identifiers for this entity.

BIT-libphp-2026-91767osv
BIT-php-2026-91767osv
BIT-php-min-2026-91767osv

sources

Which sources assert this record, and when.

osv cert_bund nvd NVD CVE.org MITRE

published 2026-09-25modified 2026-10-27

references (1) nvd

External citations — patches, advisories, analysis.

https://github.com/php/php-src/security/advisories/GHSA-xr7j-rvgx-xq5pVendor Advisory

scry

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