CVE Catalog

CVE-2026-57497

MediumCVSS 5.3
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.52%

42th percentile - higher than 42% of all known CVEs

Summary

In webtransport-go prior to 0.11.1, Session.parseNextCapsule() in session.go skips an unknown WebTransport capsule on the HTTP/3 request stream by calling io.ReadAll on the capsule reader, retaining the complete declared capsule body in memory. A malicious peer can send a large unknown capsule and cause a client or server to allocate memory for the full payload, as QUIC flow control does not bound the total retained allocation. This results in memory and resource exhaustion that can disrupt or crash the affected process.

Risk Assessment

An attacker can remotely cause memory exhaustion and crash a WebTransport client or server, resulting in denial of service. The risk affects applications using webtransport-go prior to version 0.11.1.

Recommendation

Upgrade the webtransport-go library to version 0.11.1 or later. Until then, consider limiting the size of processed capsules or monitoring memory usage.

Related vulnerabilities

Original NVD description (English source)

webtransport-go is an implementation of the WebTransport protocol. Prior to 0.11.1, Session.parseNextCapsule() in session.go skips an unknown WebTransport capsule on the HTTP/3 request stream by calling io.ReadAll on the capsule reader, retaining the complete declared capsule body in memory. A malicious peer can send a large unknown capsule and cause a client or server to allocate memory for the full payload; QUIC flow control does not bound the total retained allocation because reading advances the flow-control window while the received bytes remain in memory. The resulting memory and resource exhaustion can disrupt or crash the affected process. This issue is fixed in version 0.11.1.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS