CVE-2026-56853

Summary

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.

Affected Software

VendorProductVersion RangeStatus
Go standard librarynet/http0 < 1.25.13affected
Go standard librarynet/http1.26.0-0 < 1.26.6affected
Go standard librarynet/http1.27.0-0 < 1.27.0-rc.3affected

Weaknesses

  • CWE-770: Allocation of Resources Without Limits or Throttling

References