---
cve: "CVE-2026-91769"
severity: "MEDIUM"
cvss: 4.3
epss: "0.1%"
vendor: "PHP Group"
kev: false
exploited: false
published: "2026-09-25 21:17:24"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-10-02T21:27:43+02:00"
---

# CVE-2026-91769

> 4.3 MEDIUM · 🧪 PoC

## Beschreibung

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.

## CNA-Record (Kanon, cvelistV5)

- CNA: **php**
- State: PUBLISHED
- Stand: 2026-09-28 13:31:31
- CNA-CVSS: **4.3** (`CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N`)

## CISA-Anreicherung (vulnrichment/ADP)

- CISA-SSVC (Coordinator, v2.0.3):
  - Exploitation: **none**
  - Automatable: **no**
  - Technical Impact: **partial**

## CVSS-Vektor

```
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Benachbart | warn |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |
| S Scope | Unverändert | good |
| C Vertraulichkeit | Gering | warn |
| I Integrität | Keine | good |
| A Verfügbarkeit | Keine | good |

## BSI-Hinweise (deutsch)

- [PHP: Mehrere Schwachstellen](https://wid.cert-bund.de/portal/wid/sicherheitshinweis/WID-SEC-W-2026-3585) — _BSI-Einstufung: mittel_
  Ein Angreifer kann mehrere Schwachstellen in PHP ausnutzen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen oder die Integrität zu verletzen.

## Referenzen

- <https://github.com/php/php-src/security/advisories/GHSA-vvx9-73fr-5jjx>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-91769) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_