CVE catalog

CVE-2026-63380

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

[CVE catalog]

Severity: Medium · CVSS 5.7CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Published: Aug 20, 2026, 5:52:29 PM UTC
Updated: Aug 20, 2026, 6:16:35 PM UTC
Source: [NVD] · [CVE record]
EPSS: 0.14% · Oct 25, 2026

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.

Vulnerable and fixed packages

Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.

Distribution	Package	Release	Version	Status
Debian	libevent	sid	`2.1.13-stable-1`	not affected
Debian	libevent	forky	`2.1.13-stable-1`	not affected
Debian	libevent	trixie	`2.1.12-stable-10`	not affected
Debian	libevent	trixie-security	`2.1.13-stable-1~deb13u1`	not affected
Debian	libevent	bookworm	`2.1.12-stable-8`	not affected
Debian	libevent	bookworm-security	`2.1.12-stable-8+deb12u1`	not affected

Fixed-version evidence

Distribution	Package	Type	Release	Fixed version	Urgency	Origin	Bugs
Debian	libevent	source	sid	`Not affected`	unimportant	Not reported	Not reported
Debian	libevent	source	forky	`Not affected`	unimportant	Not reported	Not reported
Debian	libevent	source	trixie	`Not affected`	unimportant	Not reported	Not reported
Debian	libevent	source	bookworm	`Not affected`	unimportant	Not reported	Not reported

OpenFactory catalog packages

[Debian 12 (Bookworm)]

[libevent-2.1-7]Not affected
Source package: [libevent]
Details (2)
- 2.1.12-stable-8 · amd64 · bookworm
  Not affected
  nvd · libevent · debian · bookworm
- 2.1.12-stable-8 · arm64 · bookworm
  Not affected
  nvd · libevent · debian · bookworm
[libevent-core-2.1-7]Not affected
Source package: [libevent]
Details (2)
- 2.1.12-stable-8 · amd64 · bookworm
  Not affected
  nvd · libevent · debian · bookworm
- 2.1.12-stable-8 · arm64 · bookworm
  Not affected
  nvd · libevent · debian · bookworm
[libevent-dev]Not affected
Source package: [libevent]
Details (2)
- 2.1.12-stable-8 · amd64 · bookworm
  Not affected
  nvd · libevent · debian · bookworm
- 2.1.12-stable-8 · arm64 · bookworm
  Not affected
  nvd · libevent · debian · bookworm
[libevent-extra-2.1-7]Not affected
Source package: [libevent]
Details (2)
- 2.1.12-stable-8 · amd64 · bookworm
  Not affected
  nvd · libevent · debian · bookworm
- 2.1.12-stable-8 · arm64 · bookworm
  Not affected
  nvd · libevent · debian · bookworm
[libevent-openssl-2.1-7]Not affected
Source package: [libevent]
Details (2)
- 2.1.12-stable-8 · amd64 · bookworm
  Not affected
  nvd · libevent · debian · bookworm
- 2.1.12-stable-8 · arm64 · bookworm
  Not affected
  nvd · libevent · debian · bookworm
[libevent-pthreads-2.1-7]Not affected
Source package: [libevent]
Details (2)
- 2.1.12-stable-8 · amd64 · bookworm
  Not affected
  nvd · libevent · debian · bookworm
- 2.1.12-stable-8 · arm64 · bookworm
  Not affected
  nvd · libevent · debian · bookworm

Observed: Oct 27, 2026, 7:04:26 AM UTC

References

[Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [Red Hat security advisories and VEX]