CVE-2026-56853
Apply ReadHeaderTimeout when doing unencrypted HTTP/2 check in net/http
HIGH 7.5
At a glance
- Source
- NVD
- EPSS
- EPSS 0.57 % · percentile 47 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- Go
- NVD status
- Awaiting Analysis
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.
Weaknesses (CWE)
- CWE-770 — Allocation of Resources Without Limits or Throttling
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | CISA-ADP |
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | NVD · 134c704f-9b21-4f2e-91b3-4a467353bcc0 (Secondary) |
Advisories
- GO-2026-6089 — Apply ReadHeaderTimeout when doing unencrypted HTTP/2 check in net/http
European references
- ENISA EUVD · EUVD-2026-58510
- GCVE · GCVE-0-2026-56853
CERT-FR advisories
- CERTFR-2026-AVI-1385 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1249 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1125 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
Affected products
| Product | Versions |
|---|---|
| Go standard library · net/http | affected 0 < 1.25.13 ; affected 1.26.0-0 < 1.26.6 ; affected 1.27.0-0 < 1.27.0-rc.3 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |