{"id":"CVE-2026-57497","summary":"webtransport-go: Memory Exhaustion Attack due to Buffering of Unknown Capsules","details":"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.","aliases":["GHSA-g35j-m5xg-vh3q","GO-2026-6099"],"modified":"2026-09-15T11:30:44.014940398Z","published":"2026-09-14T16:05:31.661Z","related":["openSUSE-SU-2026:21761-1"],"database_specific":{"cwe_ids":["CWE-770"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/57xxx/CVE-2026-57497.json","cna_assigner":"GitHub_M"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/57xxx/CVE-2026-57497.json"},{"type":"FIX","url":"https://github.com/quic-go/webtransport-go/commit/3aecd11736579530ff067651c30a543eb0b4b8c4"},{"type":"FIX","url":"https://github.com/quic-go/webtransport-go/pull/290"},{"type":"WEB","url":"https://github.com/quic-go/webtransport-go/releases/tag/v0.11.1"},{"type":"ADVISORY","url":"https://github.com/quic-go/webtransport-go/security/advisories/GHSA-g35j-m5xg-vh3q"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-57497"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/quic-go/webtransport-go","events":[{"introduced":"0"},{"fixed":"d03fbc34952e05e833ab2a3810ab55aeefe2bf30"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"fixed":"0.11.1"}],"source":"AFFECTED_FIELD"}}],"versions":["v0.11.0","v0.10.0","v0.9.0","v0.8.0","v0.7.0","v0.6.0","v0.5.3","v0.5.2","v0.5.1","v0.5.0","v0.4.3","v0.4.2","v0.4.1","v0.4.0","v0.3.0","v0.2.0","v0.1.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-57497.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"}]}