CVE-2026-15711
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.
CSIRTS triage
- What
- There is a remote denial of service vulnerability via oversized control frame protocol violation.
- Who is affected
- Deployments of libsoup are affected.
- Urgency
- Remediation is urgent due to the high severity of the vulnerability.
- Action
- Upgrade to a patched version of libsoup.
AI-assisted analysis generated from the source advisory — verify against the original.
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Exploitation outlook
- Low exploitation risk0.43% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 35% of all EPSS-scored CVEs.
Advisory coverage (2)
External references
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