CVE-2026-21435
webtransport-go: CloseWithError can block indefinitely in github.com/quic-go/webtransport-go
5.3
MEDIUM
CVSS 3.1
EPSS 0.02%
Description
webtransport-go: CloseWithError can block indefinitely in github.com/quic-go/webtransport-go
How to fix CVE-2026-21435
To remediate CVE-2026-21435, upgrade the affected package to a fixed version below.
- Go/github.com/quic-go/webtransport-go—upgrade to 0.10.0 or later
- —upgrade to 0.10.0 or later
Is CVE-2026-21435 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- from 0, < 0.10.0
- from 0, < 0.10.0
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |