CVE-2026-56853

HighCVSS 7.5/10Last modified Sep 3, 2026

Description

When a server is configured to support unencrypted HTTP/2, it reads a few bytes from each new connection to see if they contain the HTTP/2 client preface. ReadHeaderTimeout is unexpectedly not being applied when doing this.

Metrics

CVSS 3.1 7.5/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weakness enumeration

CWE-770

Affected software

Source: the vendor's advisory (CNA). NVD analysis pending.

No affected versions have been published.

Timeline

Published: Aug 13, 2026
Last modified: Sep 3, 2026
NVD status: Awaiting Analysis

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