Allocation of Resources Without Limits or Throttling The advisory has been revoked - it doesn't affect any version of package libevent  (opens in a new tab)


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EPSS
0.61% (47th percentile)

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  • Snyk IDSNYK-RHEL8-LIBEVENT-19405171
  • published28 Aug 2026
  • disclosed20 Aug 2026

Introduced: 20 Aug 2026

CVE-2026-63495  (opens in a new tab)
CWE-770  (opens in a new tab)

Amendment

The Red Hat security team deemed this advisory irrelevant for RHEL:8.

NVD Description

Note: Versions mentioned in the description apply only to the upstream libevent package and not the libevent package as distributed by RHEL.

Libevent is an event notification library. From 2.2.0-alpha-dev until 2.2.2-alpha, the libevent WebSocket server in ws.c accumulates fragmented frames in evws->incomplete_frames without enforcing a total message-size limit. An unauthenticated remote client can repeatedly send fragmented WebSocket frames below WS_MAX_RECV_FRAME_SZ with FIN=0, causing the evbuffer to grow without bound until the process or host exhausts memory. This issue is fixed in version 2.2.2-alpha.