CVE-2026-91769
Description
PHP's OpenSSL stream peer verification checks the certificate's subjectAltName entries first and, whenever no entry matches, falls back to the Common Name. RFC 6125 requires the CN to be ignored once the certificate presents any service identity, so a certificate carrying a non-matching DNS SAN was still accepted when its CN matched the requested peer_name. A certificate trusted by the client for one name can therefore be used to impersonate another.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
Propose a mitigation on Community Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
Debian Affected 4 releases
| Version | Status | Fixed in |
|---|---|---|
| trixie | Affected | — |
| sid | Affected | — |
| forky | Affected | — |
| bookworm | Affected | — |
Alpine Fixed 1 release
| Version | Status | Fixed in |
|---|---|---|
| v3.24 | Fixed | 8.3.35-r0 |
References
- https://security-tracker.debian.org/tracker/CVE-2026-91769
- https://security.alpinelinux.org/vuln/CVE-2026-91769
- https://pkgs.alpinelinux.org/packages?name=php83
- https://pkgs.alpinelinux.org/packages?name=php84
- https://pkgs.alpinelinux.org/packages?name=php85
- https://github.com/php/php-src/security/advisories/GHSA-vvx9-73fr-5jjx
CWEs
CWE-297
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.