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7.5 High

CVE-2026-56853 When a server is configured to support unencrypted HTTP/2, it reads a few bytes from each new connection to see if…

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.

Affected products and versions

Product Affected versions Fixed in
net/http 1.27 earliest → < 1.27.0-rc.3 1.27.0-rc.3
net/http 1.26 1.26.0-0 → < 1.26.6 1.26.6
net/http 1.25 earliest → < 1.25.13 1.25.13

References

Timeline

  1. Published
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