CVE-2026-56853

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.

CVSS Vector

References

• https://go.dev/cl/795540
• https://go.dev/issue/80205
• https://groups.google.com/g/golang-announce/c/94pEornpRlI
• https://pkg.go.dev/vuln/GO-2026-6089