CVE-2026-56853

HIGHPre-NVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2026-08-14. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 7.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — Patch released this week
7.5EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.6%CVSS: 7.5Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

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 v3
7.5
EG Score
7.5HIGHmedium confidence
EG Risk
49
EG Risk 49/100CISA SSVC

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity75% × 45%
Exploitation1% × 40%
Automatability100% × 15%
CISA SSVC: Track at low or medium mission impact; Attend at high (mission-essential systems).
Action: A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
EPSS PROB
0.6%
EPSS %ILE
45th
KEV
Not listed

CISA SSVCTrack at low or medium mission impact; Attend at high (mission-essential systems).

A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table

Published

August 13, 2026

Last Modified

September 3, 2026

Advisory Details (4)

Auto-updated Aug 14, 2026
Patch available.
generic

GO-2026-6089 - Go Packages

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

net/http: enabling UnencryptedHTTP2 on Server disables first header read timeout · Issue #80205 · golang/go · GitHub

https://go.dev/issue/80205

Vendor Advisories for CVE-2026-56853(20)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(27)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
redhatquay/quay-rhel9:17906902982026-10-01redhat
redhatcompliance/openshift-file-integrity-rhel8-operator:17902892632026-09-30redhat
redhatrhoai/odh-kube-auth-proxy-rhel9:17901314762026-09-30redhat
redhatrh-lightspeed-runtimes/runtimes-inventory-rhel9-operator:17901941222026-09-29redhat
redhatmulticluster-globalhub/multicluster-globalhub-agent-rhel9:17900854942026-09-29redhat
redhatmulticluster-globalhub/multicluster-globalhub-agent-rhel9:17906386122026-09-29redhat
redhatopenshift-clients-0:4.22.0-202609170632.p2.gd0f23b1.assembly.stream.el82026-09-29redhat
redhatmicroshift-0:4.22.16-202609250657.p0.g3898bb2.assembly.4.22.16.el92026-09-29redhat
redhatgit-lfs-0:2.13.3-3.el8_6.82026-09-28redhat
redhatmulticluster-engine/discovery-rhel9:17901212872026-09-28redhat
redhatrhacm2/thanos-rhel9:17901984082026-09-28redhat
redhatgit-lfs-0:3.2.0-2.el8_8.82026-09-28redhat
redhatrhacm2/thanos-rhel9:17901781062026-09-28redhat
redhatbuildah-2:1.43.3-2.el9_82026-09-24redhat
redhatskopeo-2:1.22.2-8.el9_82026-09-24redhat
redhatmulticluster-globalhub/multicluster-globalhub-agent-rhel9:17895154082026-09-24redhat
redhatopenshift-logging/eventrouter-rhel9:17896591452026-09-23redhat
redhatansible-automation-platform-26/receptor-rhel9:17896101202026-09-23redhat
redhatcontainernetworking-plugins-1:1.9.0-4.el9_82026-09-23redhat
redhatnetwork-observability/network-observability-cli-rhel9:17899862792026-09-23redhat
redhatreceptor-0:1.6.8-1.el9ap2026-09-23redhat
redhatrhc-worker-playbook-0:0.2.3-6.el10_0.12026-09-22redhat
redhatpodman-6:5.8.2-7.el9_82026-09-22redhat
redhatweb-terminal/web-terminal-exec-rhel9:17890570052026-09-22redhat
redhatweb-terminal/web-terminal-exec-rhel9:17889897112026-09-22redhat
redhatsource-to-image/source-to-image-rhel8:17900599562026-09-22redhat
redhatopenshift-builds/openshift-builds-waiters-rhel9:17899759252026-09-22redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(6 across 4 ecosystems)
Debian:14(3)
PackageVulnerable rangeFix by version rangeDependents
golang-1.251.25.0-1 ... 1.25.9-1 (20 versions)
  • every version on: no fix on record
—
golang-1.261.26.0-1 ... 1.26~rc3-2 (16 versions)
  • every version up to 1.26.6-1: fixed in 1.26.6-1
—
golang-1.271.27~rc1-1, 1.27~rc2-1
  • every version up to 1.27~rc3-1: fixed in 1.27~rc3-1
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
golang-1.191.19.10-1 ... 1.19.9-1 (12 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
golang-1.241.24.12-1 ... 1.24.9-1 (10 versions)
  • every version on: no fix on record
—
Go(1)
PackageVulnerable rangeFix by version rangeDependents
stdlib—
  • every version up to 1.25.13: fixed in 1.25.13
  • 1.26.0-0 up to 1.26.6: fixed in 1.26.6
  • 1.27.0-0 up to 1.27.0-rc.3: fixed in 1.27.0-rc.3
—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

All Vendor Advisories

(25)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 30× in last 7d / 139× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 262 total refreshes for this CVE.

  1. 2026-10-04 23:22 UTCEPSS rescore
  2. 2026-10-04 22:14 UTCVendor advisory
  3. 2026-10-04 22:14 UTCGHSA enrichment
  4. 2026-10-04 08:30 UTCVendor advisory
  5. 2026-10-04 08:30 UTCGHSA enrichment
  6. 2026-10-03 19:43 UTCEG score recompute
  7. 2026-10-03 19:43 UTCVendor advisory
  8. 2026-10-03 19:43 UTCGHSA enrichment
  9. 2026-10-03 14:26 UTCEPSS rescore
  10. 2026-10-02 21:51 UTCEG score recompute
  11. 2026-10-02 21:51 UTCVendor advisory
  12. 2026-10-02 21:51 UTCGHSA enrichment
  13. 2026-10-02 17:56 UTCEPSS rescore
  14. 2026-10-02 07:24 UTCEG score recompute
  15. 2026-10-02 07:24 UTCVendor advisory
  16. 2026-10-02 07:24 UTCGHSA enrichment
  17. 2026-10-01 19:50 UTCEPSS rescore
  18. 2026-10-01 10:29 UTCVendor advisory
  19. 2026-10-01 10:29 UTCGHSA enrichment
  20. 2026-09-30 21:43 UTCEG score recompute
  21. 2026-09-30 21:43 UTCVendor advisory
  22. 2026-09-30 21:43 UTCGHSA enrichment
  23. 2026-09-30 15:03 UTCEPSS rescore
  24. 2026-09-29 15:22 UTCEPSS rescore
  25. 2026-09-29 03:24 UTCEG score recompute
Show 75 more
  1. 2026-09-29 03:24 UTCVendor advisory
  2. 2026-09-29 03:24 UTCGHSA enrichment
  3. 2026-09-28 13:51 UTCEPSS rescore
  4. 2026-09-28 13:19 UTCVendor advisory
  5. 2026-09-28 13:19 UTCGHSA enrichment
  6. 2026-09-28 00:33 UTCEG score recompute
  7. 2026-09-28 00:33 UTCVendor advisory
  8. 2026-09-28 00:33 UTCGHSA enrichment
  9. 2026-09-27 13:48 UTCEPSS rescore
  10. 2026-09-27 09:40 UTCEG score recompute
  11. 2026-09-27 09:40 UTCVendor advisory
  12. 2026-09-27 09:40 UTCGHSA enrichment
  13. 2026-09-26 15:59 UTCEPSS rescore
  14. 2026-09-25 03:25 UTCEG score recompute
  15. 2026-09-25 03:25 UTCVendor advisory
  16. 2026-09-25 03:25 UTCGHSA enrichment
  17. 2026-09-24 14:04 UTCEPSS rescore
  18. 2026-09-24 01:25 UTCEG score recompute
  19. 2026-09-24 01:25 UTCVendor advisory
  20. 2026-09-24 01:24 UTCGHSA enrichment
  21. 2026-09-23 17:54 UTCEPSS rescore
  22. 2026-09-23 12:38 UTCVendor advisory
  23. 2026-09-23 12:37 UTCGHSA enrichment
  24. 2026-09-22 23:49 UTCEG score recompute
  25. 2026-09-22 23:49 UTCVendor advisory
  26. 2026-09-22 23:49 UTCGHSA enrichment
  27. 2026-09-22 10:58 UTCVendor advisory
  28. 2026-09-22 10:58 UTCGHSA enrichment
  29. 2026-09-21 22:11 UTCEG score recompute
  30. 2026-09-21 22:11 UTCVendor advisory
  31. 2026-09-21 22:11 UTCGHSA enrichment
  32. 2026-09-21 09:24 UTCEG score recompute
  33. 2026-09-21 09:24 UTCVendor advisory
  34. 2026-09-21 09:24 UTCGHSA enrichment
  35. 2026-09-20 20:16 UTCEPSS rescore
  36. 2026-09-20 18:48 UTCVendor advisory
  37. 2026-09-20 18:48 UTCGHSA enrichment
  38. 2026-09-20 05:10 UTCVendor advisory
  39. 2026-09-20 05:10 UTCGHSA enrichment
  40. 2026-09-19 16:24 UTCEG score recompute
  41. 2026-09-19 16:24 UTCVendor advisory
  42. 2026-09-19 16:24 UTCGHSA enrichment
  43. 2026-09-19 03:38 UTCEG score recompute
  44. 2026-09-19 03:38 UTCVendor advisory
  45. 2026-09-19 03:38 UTCGHSA enrichment
  46. 2026-09-18 19:28 UTCEPSS rescore
  47. 2026-09-18 14:50 UTCVendor advisory
  48. 2026-09-18 14:50 UTCGHSA enrichment
  49. 2026-09-18 02:04 UTCEG score recompute
  50. 2026-09-18 02:04 UTCVendor advisory
  51. 2026-09-18 02:04 UTCGHSA enrichment
  52. 2026-09-17 19:31 UTCEPSS rescore
  53. 2026-09-17 13:18 UTCVendor advisory
  54. 2026-09-17 13:18 UTCGHSA enrichment
  55. 2026-09-16 23:50 UTCEG score recompute
  56. 2026-09-16 23:50 UTCVendor advisory
  57. 2026-09-16 23:50 UTCGHSA enrichment
  58. 2026-09-16 14:08 UTCEPSS rescore
  59. 2026-09-16 05:15 UTCEPSS rescore
  60. 2026-09-16 05:02 UTCVendor advisory
  61. 2026-09-16 05:02 UTCGHSA enrichment
  62. 2026-09-15 15:21 UTCEG score recompute
  63. 2026-09-15 15:21 UTCVendor advisory
  64. 2026-09-15 15:21 UTCGHSA enrichment
  65. 2026-09-15 03:11 UTCEPSS rescore
  66. 2026-09-15 02:15 UTCVendor advisory
  67. 2026-09-15 02:15 UTCGHSA enrichment
  68. 2026-09-14 13:22 UTCVendor advisory
  69. 2026-09-14 13:22 UTCGHSA enrichment
  70. 2026-09-14 00:33 UTCEG score recompute
  71. 2026-09-14 00:33 UTCVendor advisory
  72. 2026-09-14 00:33 UTCGHSA enrichment
  73. 2026-09-13 16:47 UTCEPSS rescore
  74. 2026-09-13 11:46 UTCEG score recompute
  75. 2026-09-13 11:46 UTCVendor advisory

Related CVEs(same product + same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-56853?
CVE-2026-56853 is a high vulnerability published on August 13, 2026. 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.
When was CVE-2026-56853 disclosed?
CVE-2026-56853 was first published on August 13, 2026, with the most recent update on September 3, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-56853 actively exploited?
CVE-2026-56853 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.6% probability of exploitation in the next 30 days (45th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-56853?
CVE-2026-56853 has a CVSS v3.1 base score of 7.5 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-56853?
A fix for CVE-2026-56853 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-56853 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-56853

Explore →

Is Your Infrastructure Affected by CVE-2026-56853?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Book a Demo →Browse All CVEs