CVE-2026-21435

HIGH EPSS 33.0%
Published Feb 12, 20264mo ago · Modified Jun 17, 20261w ago
7.5 CVSS 3.1
High
Find Similar
Published Feb 12, 2026 4mo ago
Last Modified Jun 17, 2026 1w ago

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.

CVSS Details

Base Score
7.5
Exploitability
3.9
Impact
3.6
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High

Threat Intelligence

EPSS Exploit Probability
33.0% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available

Weaknesses 1

CWE-400 Uncontrolled Resource Consumption Resource Mgmt

Affected Products 1

VendorProductVersionRange
quic-gowebtransport-go* <0.10.0

References 2

  • github.com https://github.com/quic-go/webtransport-go/releases/tag/v0.10.0
    ProductRelease Notes
  • github.com https://github.com/quic-go/webtransport-go/security/advisories/GHSA-px4r-g4p3-hhqv
    Vendor Advisory

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.