CVE-2026-57497: quic-go webtransport-go · Unthrottled Resource Allocation
Affects quic-go webtransport-goSource CVE Database V5
Not known to be exploited · CVSS 5.3 Medium : upgrade to 0.11.1 when convenient.
Data as of 30 Oct 2026, 06:59 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 44% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 0.11.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:LExploitation evidence
Disclosed: evidence found.
CVE published 14 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Upgrade webtransport-go and github.com/quic-go/webtransport-go to 0.11.1.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| quic-gowebtransport-go | Affected
| Fixed in
|
Gogithub.com/quic-go/webtransport-gopkg:golang/github.com/quic-go/webtransport-goOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade to webtransport-go version 0.11.1 or later, where this issue is fixed. No other mitigations are specified. Patch status is confirmed fixed in 0.11.1.
Description
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.
References
- github.com/quic-go/webtransport-go/security/advisories/GHSA-g35j-m5xg-vh3q (opens in a new tab)
- github.com/quic-go/webtransport-go/pull/290 (opens in a new tab)
- github.com/quic-go/webtransport-go/commit/3aecd11736579530ff067651c30a543eb0b4b8c4 (opens in a new tab)
- github.com/quic-go/webtransport-go/releases/tag/v0.11.1 (opens in a new tab)