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Fencer Vulns
medium 6.5

CVE-2026-91767 json

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

published 2026-09-24 45 d ago modified 2026-10-29 10 d ago also BIT-libphp-2026-91767 , BIT-php-2026-91767 , BIT-php-min-2026-91767 , EUVD-2026-87343 , GHSA-xr7j-rvgx-xq5p

cvss
6.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.1%
EPSS 0.1% chance of exploitation in 30 days, percentile 1%
public exploits
0
none known

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.

Patch / fix

  • bitnami libphp 8.2.34, 8.3.35, 8.4.26, 8.5.11
  • bitnami php 8.2.34, 8.3.35, 8.4.26, 8.5.11
  • bitnami php-min 8.2.34, 8.3.35, 8.4.26, 8.5.11
  • PHP Group PHP 8.2.34, 8.3.35, 8.4.26, 8.5.11
  • php8.2 Debian 12 8.2.34-1~deb12u1
  • php8.4 Debian 13 8.4.26-1~deb13u1
  • php8.4 Debian 14 8.4.26-1

debian advisories DEBIAN-CVE-2026-91767

  • php8.1 Ubuntu 22.04 LTS 8.1.2-1ubuntu2.27
  • php8.3 Ubuntu 24.04 LTS 8.3.6-0ubuntu0.24.04.12
  • php8.5 Ubuntu 26.10 8.5.9-0ubuntu2
  • php8.5 Ubuntu 26.04 LTS 8.5.4-0ubuntu1.4
  • php7.0 Ubuntu Pro 16.04 LTS 7.0.33-0ubuntu0.16.04.16+esm21
  • php7.2 Ubuntu Pro 18.04 LTS 7.2.24-0ubuntu0.18.04.17+esm13
  • php7.4 Ubuntu Pro 20.04 LTS 7.4.3-4ubuntu2.29+esm4

ubuntu advisories UBUNTU-CVE-2026-91767

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • php hummingbird 1 8.5.11-2.hum1
  • php-gd hummingbird 1 8.5.11-2.hum1
  • php-cli hummingbird 1 8.5.11-2.hum1
  • php-dba hummingbird 1 8.5.11-2.hum1
  • php-dbg hummingbird 1 8.5.11-2.hum1
  • php-ffi hummingbird 1 8.5.11-2.hum1
  • php-fpm hummingbird 1 8.5.11-2.hum1
  • php-gmp hummingbird 1 8.5.11-2.hum1

red hat advisories RHSA-2026:70720

  • php7 SLES for SAP 15 SP6, SLES for SAP 15 SP5, SLES for SAP 15 SP4 +7 more 7.4.33-150400.4.81.1
  • php7-fpm SLES for SAP 15 SP6, SLES for SAP 15 SP5, SLES for SAP 15 SP4 +6 more 7.4.33-150400.4.81.1
  • php7-test SLE Module for Package Hub 15 SP7 7.4.33-150400.4.81.2
  • php7-embed SLE Module for Package Hub 15 SP7 7.4.33-150400.4.81.1
  • php7-fastcgi SLES for SAP 15 SP6, SLES for SAP 15 SP5, SLES for SAP 15 SP4 +6 more 7.4.33-150400.4.81.1
  • apache2-mod_php7 SLES for SAP 15 SP6, SLES for SAP 15 SP5, SLES for SAP 15 SP4 +7 more 7.4.33-150400.4.81.1
  • php8 SLES for SAP 15 SP5, SLES for SAP 15 SP4, SLES 15 SP5-LTSS +5 more 8.0.30-150400.4.76.1
  • php8-fpm SLES for SAP 15 SP5, SLES for SAP 15 SP4, SLES 15 SP5-LTSS +5 more 8.0.30-150400.4.76.1

suse advisories SUSE-SU-2026:4853-1SUSE-SU-2026:4651-1SUSE-SU-2026:4603-1SUSE-SU-2026:4602-1SUSE-SU-2026:24158-1

  • php8 openSUSE Leap 16.0 8.4.26-160000.1.1
  • php8-fpm openSUSE Leap 16.0 8.4.26-160000.1.1
  • php8-test openSUSE Leap 16.0 8.4.26-160000.1.1
  • php8-embed openSUSE Leap 16.0 8.4.26-160000.1.1
  • php8-fastcgi openSUSE Leap 16.0 8.4.26-160000.1.1
  • apache2-mod_php8 openSUSE Leap 16.0 8.4.26-160000.1.1
  • php8 openSUSE Tumbleweed 8.5.11-1.1

opensuse advisories openSUSE-SU-2026:22045-1openSUSE-SU-2026:11901-1

  • php AlmaLinux 8 7.4.33-8.module_el8.10.0+4321+cf5fd4bb
  • libzip AlmaLinux 8 1.6.1-1.module_el8.6.0+2750+78feabcb
  • libzip AlmaLinux 8 1.6.1-1.module_el8.6.0+3239+bedf0508
  • libzip AlmaLinux 8 1.6.1-1.module_el8.10.0+3935+28808425
  • php-gd AlmaLinux 8 7.4.33-8.module_el8.10.0+4321+cf5fd4bb
  • php-cli AlmaLinux 8 7.4.33-8.module_el8.10.0+4321+cf5fd4bb
  • php-dba AlmaLinux 8 7.4.33-8.module_el8.10.0+4321+cf5fd4bb
  • php-dbg AlmaLinux 8 7.4.33-8.module_el8.10.0+4321+cf5fd4bb

almalinux advisories ALSA-2026:87080

  • php Rocky Linux 8 7.4.33-8.module+el8.10.0+40393+c071e357
  • libzip Rocky Linux 8 1.6.1-1.module+el8.10.0+1912+72767185
  • libzip Rocky Linux 8 1.6.1-1.module+el8.10.0+1604+6558efc7
  • php-pear Rocky Linux 8 1:1.10.13-1.module+el8.10.0+1912+72767185
  • php-pear Rocky Linux 8 1:1.10.13-1.module+el8.10.0+1605+02e07af7
  • php-pear Rocky Linux 8 1:1.10.13-1.module+el8.10.0+1604+6558efc7
  • php-pecl-rrd Rocky Linux 8 2.0.1-1.module+el8.10.0+1604+6558efc7
  • php-pecl-rrd Rocky Linux 8 2.0.1-1.module+el8.10.0+1912+72767185

rocky linux advisories RLSA-2026:87080

  • php82 Alpine 3.22 8.2.35-r0
  • php83 Alpine 3.23, Alpine 3.22 8.3.36-r0
  • php83 Alpine 3.24 8.3.35-r0
  • php84 Alpine 3.23, Alpine 3.22 8.4.27-r0
  • php84 Alpine 3.24 8.4.26-r0
  • php85 Alpine 3.23 8.5.12-r0
  • php85 Alpine 3.24 8.5.11-r0

alpine advisories ALPINE-CVE-2026-91767

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-91767 updated cvss 6.5

php: php: Information disclosure via crafted TLS server certificate

  • Red Hat Enterprise Linux 6 php, php-gd, php-cli, php-dba, php-fpm, php-pdo, +21 more
    affected: workaround, no fix planned “Restrict outbound TLS connections from PHP applications to trusted servers and certificate authorities. Do not disable verify_peer_name as a workaround except after an explicit risk review.”
  • Red Hat Enterprise Linux 7 php, php-gd, php-cli, php-dba, php-fpm, php-pdo, +19 more Red Hat Enterprise Linux 8 php, libzip, php-gd, php-cli, php-dba, php-dbg, +30 more Red Hat Enterprise Linux 9 php, php-gd, php-cli, php-dba, php-dbg, php-ffi, +19 more Red Hat Enterprise Linux 10 php 8.3.33-1.el10_2, php8.4 8.4.24-2.el10
    affected: workaround, no fix available “Restrict outbound TLS connections from PHP applications to trusted servers and certificate authorities. Do not disable verify_peer_name as a workaround except after an explicit risk review.”
  • Red Hat Enterprise Linux AppStream (v. 8) php 7.4.33-8.module+el8.10.0+25117+30337cca, libzip 1.6.1-1.module+el8.10.0+22485+a3539972, php-gd 7.4.33-8.module+el8.10.0+25117+30337cca, php-cli 7.4.33-8.module+el8.10.0+25117+30337cca, php-dba 7.4.33-8.module+el8.10.0+25117+30337cca, php-dbg 7.4.33-8.module+el8.10.0+25117+30337cca, +28 more
    fixed: vendor fix “Restrict outbound TLS connections from PHP applications to trusted servers and certificate authorities. Do not disable verify_peer_name as a workaround except after an explicit risk review.” RHSA-2026:87080
  • Red Hat Hardened Images php 8.5.11-2.hum1, php-gd 8.5.11-2.hum1, php-cli 8.5.11-2.hum1, php-dba 8.5.11-2.hum1, php-dbg 8.5.11-2.hum1, php-ffi 8.5.11-2.hum1, +21 more
    fixed: vendor fix “Restrict outbound TLS connections from PHP applications to trusted servers and certificate authorities. Do not disable verify_peer_name as a workaround except after an explicit risk review.” RHSA-2026:70720

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
41 d ago

Exploit prediction

0.11% chance of exploitation in the next 30 days, higher than 1% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 6.5 CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
NVD 3.1 6.5 CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
OSV 3.1 6.5 CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem package affected fixed in
bitnami libphp
>=8.2.0, <8.2.34
>=8.3.0, <8.3.35
>=8.4.0, <8.4.26
>=8.5.0, <8.5.11
8.2.34
8.3.35
8.4.26
8.5.11
bitnami php
>=8.2.0, <8.2.34
>=8.3.0, <8.3.35
>=8.4.0, <8.4.26
>=8.5.0, <8.5.11
8.2.34
8.3.35
8.4.26
8.5.11
bitnami php-min
>=8.2.0, <8.2.34
>=8.3.0, <8.3.35
>=8.4.0, <8.4.26
>=8.5.0, <8.5.11
8.2.34
8.3.35
8.4.26
8.5.11

Affected products

  • PHP Group PHP

Classification

Weakness
  • CWE-122 Heap-based Buffer Overflow
Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

The maintainers of php/php-src published their own advisory on GitHub. Reviewed sources take precedence over it.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.