CVE-2026-57497: medium-severity vulnerability in quic-go webtransport-go
webtransport-go: Memory Exhaustion Attack due to Buffering of Unknown Capsules
Published
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 5.3epss 0.5%
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Affected products
quic-go · webtransport-goRelated CVEs — quic-go webtransport-go
In the same product, most dangerous first.
CVE-2026-21435MEDIUMwebtransport-go CloseWithError can block indefinitelyEPSS 0.5%CVE-2026-21434MEDIUMwebtransport-go affected by Memory Exhaustion Attack due to Missing Length Check in WT_CLOSE_SESSION CapsuleEPSS 0.5%CVE-2026-21438MEDIUMwebtransport-go affected by a Memory Exhaustion Attack due to Missing Cleanup of Streams MapEPSS 0.4%