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CVE-2026-21435

NVD

https://nvd.nist.gov/vuln/detail/CVE-2026-21435

Severity

5.3

Medium

CVSS V3

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Summary

webtransport-go CloseWithError can block indefinitely

Description

webtransport-go is an implementation of the WebTransport protocol. Prior to v0.10.0, an attacker can cause a denial of service in webtransport-go by preventing or indefinitely delaying WebTransport session closure. A malicious peer can withhold QUIC flow control credit on the CONNECT stream, blocking transmission of the WT_CLOSE_SESSION capsule and causing the close operation to hang. This vulnerability is fixed in v0.10.0.

References

Affected packages

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