CVE-2026-63380 (GCVE-0-2026-63380)

Vulnerability from cvelistv5 – Published: 2026-08-20 17:52 – Updated: 2026-08-25 15:11
VLAI
Title
Libevent: Null Pointer Dereference in `evws_new_session`
Summary
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.
Severity
5.7 (Medium)
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
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-25 15:10 UTC
CWE
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7771 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
libevent libevent Affected: < 2.2.2-alpha
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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