CVE EVIDENCE REVIEW
ReviewHighEvidence review

CVE-2026-63495 evidence review

libevent

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.

Open CVE record
Evidence review

This record remains available for product and version identification, but it is not presented as a complete remediation procedure. Confirm the affected range and the supported fix in a direct vendor advisory before changing production systems.

Productlibevent
Affected versions>= >= 2.2.0-alpha-dev, < 2.2.2-alpha
Fixed versionsNo verified fixed-version field is available yet
Priority basisReview · CVSS 7.5 · EPSS -
01

Identify the product and installed version

Record whether libevent is present, where it is installed, and which interfaces are exposed.

  • Record the product name, package or appliance identifier, and installed version.
  • Identify internet-facing, administrative, API, and internal access paths.
  • Preserve the pre-change configuration and relevant service logs.
02

Compare the affected range

Use the current record as an identification aid: >= >= 2.2.0-alpha-dev, < 2.2.2-alpha. Resolve incomplete inventory results before deciding that an asset is unaffected.

03

Verify the authoritative remediation source

Open the linked source material and locate a direct vendor advisory for this CVE. Confirm the supported fixed release and product-specific update path before making a production change.

Operational boundary

This page does not replace the vendor advisory, support contract, change-management process, or recovery plan. Do not infer that an asset is unaffected from an incomplete inventory query or a missing fixed-version field.