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CVE-2025-11677 (GCVE-0-2025-11677)

Vulnerability from cvelistv5 – Published: 2025-10-20 13:41 – Updated: 2025-10-24 10:54
VLAI
Title
Use After Free in libwebsockets WebSocket server
Summary
Use After Free in WebSocket server implementation in lws_handshake_server in warmcat libwebsockets may allow an attacker, in specific configurations where the user provides a callback function that handles LWS_CALLBACK_HTTP_CONFIRM_UPGRADE, to achieve denial of service.
Severity
6.3 (Medium)
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-10-20 13:53 UTC
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
warmcat libwebsockets Affected: 3 , ≤ 4.4.1,4.3.6 (semver)
    cpe:2.3:a:warmcat:libwebsockets:*:*:*:*:*:*:*:*
Create a notification for this product.
Credits
Raffaele Bova at Nozomi Networks
Show details on NVD website
To clipboard 

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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