---
cve: "CVE-2026-63380"
severity: "MEDIUM"
cvss: 5.7
epss: "0.1%"
vendor: "libevent"
kev: false
exploited: false
published: "2026-08-20 18:16:35"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-27T22:58:27+02:00"
---

# CVE-2026-63380

> 5.7 MEDIUM · 🧪 PoC

## Beschreibung

Libevent is an event notification library. Prior to 2.2.2-alpha, libevent can dereference invalid list pointers in ws.c when evws_new_session enters its error path after evhttp_start_ws_ succeeds but bufferevent_enable_locking_ fails. evws_connection_free sees a non-null http_server and unconditionally calls TAILQ_REMOVE even though the session was never inserted into http_server->ws_sessions. A local caller able to induce this allocation or locking failure can crash the process. This issue is fixed in version 2.2.2-alpha.

## CISA-Anreicherung (vulnrichment/ADP)

- CISA-SSVC (Coordinator, v2.0.3):
  - Exploitation: **poc**
  - Automatable: **no**
  - Technical Impact: **partial**

## CVSS-Vektor

```
CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Lokal | good |
| AC Komplexität | Hoch | good |
| PR Privilegien | Gering | warn |
| UI Interaktion | Keine | bad |

## Patch verfügbar (OSV)

- 825c18bd99f556b59d61200523237f264d5cc734 (Commit)
- df3ecad3a040fd6d4fad4287defe113395de6fd7 (Commit)

## Referenzen

- <https://github.com/libevent/libevent/security/advisories/GHSA-3rpf-frgx-xq34>
- <https://github.com/libevent/libevent/commit/825c18bd99f556b59d61200523237f264d5cc734>
- <https://github.com/libevent/libevent/releases/tag/release-2.2.2-alpha>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-63380) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_