CVE-2026-15711 PUBLISHED

Libsoup: soupwebsocketconnection: libsoup: websocket remote denial of service via oversized control frame protocol violation

Assigner: redhat
Reserved: 14.07.2026 Published: 14.07.2026 Updated: 15.07.2026

A vulnerability was found in libsoup's WebSocket frame parsing implementation. The library fails to validate length rules specified in RFC 6455 §5.5, which mandates that all WebSocket control frames (e.g., PING, PONG, CLOSE) contain a payload of 125 bytes or less. A remote, unauthenticated attacker can exploit this by sending a non-compliant, oversized control frame. Because the parser handles this protocol violation improperly instead of throwing an immediate connection termination error, it triggers a internal processing crash, resulting in a remote denial of service (DoS) for applications utilizing libsoup WebSockets.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS Score: 7.5

Product Status

Vendor Red Hat
Product Red Hat Enterprise Linux 10
Versions Default: affected
Vendor Red Hat
Product Red Hat Enterprise Linux 6
Versions Default: unknown
Vendor Red Hat
Product Red Hat Enterprise Linux 7
Versions Default: unknown
Vendor Red Hat
Product Red Hat Enterprise Linux 8
Versions Default: affected
Vendor Red Hat
Product Red Hat Enterprise Linux 9
Versions Default: affected

Workarounds

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

Credits

  • Red Hat would like to thank Sebastián Alba Vives (@Sebasteuo / 0xS4bb1) for reporting this issue.

References

Problem Types

  • Allocation of Resources Without Limits or Throttling CWE