CVE-2026-21435

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Source
https://cve.org/CVERecord?id=CVE-2026-21435
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-21435.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-21435
Aliases
Related
Published
2026-02-12T18:22:58.098Z
Modified
2026-02-23T12:43:59.841014Z
Severity
  • 5.3 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L CVSS Calculator
Summary
webtransport-go CloseWithError can block indefinitely
Details

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 WTCLOSESESSION capsule and causing the close operation to hang. This vulnerability is fixed in v0.10.0.

Database specific 
{
    "cwe_ids": [
        "CWE-400"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/21xxx/CVE-2026-21435.json",
    "cna_assigner": "GitHub_M"
}
References

Affected packages

Git / github.com/quic-go/webtransport-go

Affected ranges

Type
GIT
Repo
https://github.com/quic-go/webtransport-go
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
9d448b125754f4c83064afb2c586221214e55eec

Affected versions

v0.*
v0.1.0
v0.2.0
v0.3.0
v0.4.0
v0.4.1
v0.4.2
v0.4.3
v0.5.0
v0.5.1
v0.5.2
v0.5.3
v0.6.0
v0.7.0
v0.8.0
v0.9.0

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-21435.json"