CVE-2026-56864

HIGHPre-NVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.5 under CISA-ADP (Vulnrichment) CVSS v3.1 (NVD's own analysis pending). EPSS exploit probability: 0.3%, top 77% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: cisa-adp, epss
Trending — 3 sources updated 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%CVSS: 7.5Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

A malicious GOSUMDB was capable of serving arbitrary module content not contained within the transparency log. This attack allows for a coordinating GOPROXY and GOSUMDB to serve a client malicious module content that cannot be detected by evaluating the transparency log. In order to determine if you have been affected: rm -r go.sum go.work.sum vendor/ && go mod tidy

CVSS v3
7.5
EG Score
7.5(medium)
EG Risk
49(Track)
EG Risk 49/100SSVC: Track

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%
Exploitation0% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
23%
KEV
Not listed

Published

August 13, 2026

Last Modified

September 3, 2026

Advisory Details (5)

Auto-updated Aug 14, 2026
No patch confirmed yet.
generic

GO-2026-6180 - Go Packages

https://pkg.go.dev/vuln/GO-2026-6180
generic
https://go.dev/cl/815020
generic
https://go.dev/cl/815000
generic
https://groups.google.com/g/golang-announce/c/94pEornpRlI
generic

x/mod/sumdb: ignore unrelated, unauthenticated hashes in Lookup · Issue #80745 · golang/go · GitHub

https://go.dev/issue/80745

Affected Packages

(7 across 4 ecosystems)
Debian:14(3)
PackageVulnerable rangeFixed inDependents
golang-1.251.25.0-1 ... 1.25.9-1 (20 versions)——
golang-1.261.26.0-1 ... 1.26~rc3-2 (16 versions)1.26.6-1—
golang-1.271.27~rc1-1, 1.27~rc2-11.27~rc3-1—
Go(2)
PackageVulnerable rangeFixed inDependents
golang.org/x/mod—0.40.0—
toolchain—1.27.0-rc.3—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
golang-1.191.19.10-1 ... 1.19.9-1 (12 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
golang-1.241.24.12-1 ... 1.24.9-1 (10 versions)——

Weakness Classification(1)

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

All Vendor Advisories

(1)

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 26× in last 7d / 69× 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.

  1. 2026-09-19 00:59 UTCEG score recompute
  2. 2026-09-19 00:59 UTCVendor advisory
  3. 2026-09-18 19:28 UTCEPSS rescore
  4. 2026-09-18 12:48 UTCVendor advisory
  5. 2026-09-18 00:24 UTCEG score recompute
  6. 2026-09-18 00:24 UTCVendor advisory
  7. 2026-09-17 19:31 UTCEPSS rescore
  8. 2026-09-17 12:00 UTCVendor advisory
  9. 2026-09-16 23:50 UTCEG score recompute
  10. 2026-09-16 23:50 UTCVendor advisory
  11. 2026-09-16 14:08 UTCEPSS rescore
  12. 2026-09-16 10:27 UTCEG score recompute
  13. 2026-09-16 10:27 UTCVendor advisory
  14. 2026-09-16 05:15 UTCEPSS rescore
  15. 2026-09-15 21:52 UTCVendor advisory
  16. 2026-09-15 08:55 UTCEG score recompute
  17. 2026-09-15 08:55 UTCVendor advisory
  18. 2026-09-15 03:11 UTCEPSS rescore
  19. 2026-09-14 20:45 UTCVendor advisory
  20. 2026-09-14 07:16 UTCVendor advisory
  21. 2026-09-13 19:06 UTCEG score recompute
  22. 2026-09-13 19:06 UTCVendor advisory
  23. 2026-09-13 16:47 UTCEPSS rescore
  24. 2026-09-13 06:56 UTCVendor advisory
  25. 2026-09-12 18:45 UTCEG score recompute
Show 61 more
  1. 2026-09-12 18:45 UTCVendor advisory
  2. 2026-09-12 06:35 UTCVendor advisory
  3. 2026-09-11 18:22 UTCEG score recompute
  4. 2026-09-11 18:22 UTCVendor advisory
  5. 2026-09-11 14:53 UTCEPSS rescore
  6. 2026-09-10 18:01 UTCEG score recompute
  7. 2026-09-10 09:35 UTCEPSS rescore
  8. 2026-09-09 17:41 UTCVendor advisory
  9. 2026-09-09 04:51 UTCEG score recompute
  10. 2026-09-09 04:51 UTCVendor advisory
  11. 2026-09-08 22:01 UTCEPSS rescore
  12. 2026-09-08 04:37 UTCVendor advisory
  13. 2026-09-07 16:27 UTCVendor advisory
  14. 2026-09-06 19:56 UTCEG score recompute
  15. 2026-09-06 13:47 UTCEPSS rescore
  16. 2026-09-05 19:34 UTCEG score recompute
  17. 2026-09-04 19:14 UTCEG score recompute
  18. 2026-09-04 06:12 UTCEG score recompute
  19. 2026-09-04 05:07 UTCEPSS rescore
  20. 2026-09-03 00:58 UTCEG score recompute
  21. 2026-09-02 14:12 UTCEPSS rescore
  22. 2026-09-01 23:24 UTCEG score recompute
  23. 2026-09-01 13:54 UTCEPSS rescore
  24. 2026-09-01 11:14 UTCEG score recompute
  25. 2026-09-01 04:40 UTCEPSS rescore
  26. 2026-08-30 20:41 UTCEG score recompute
  27. 2026-08-30 19:17 UTCEPSS rescore
  28. 2026-08-30 08:31 UTCEG score recompute
  29. 2026-08-30 01:22 UTCEPSS rescore
  30. 2026-08-29 06:58 UTCEG score recompute
  31. 2026-08-28 21:42 UTCEPSS rescore
  32. 2026-08-27 22:47 UTCEG score recompute
  33. 2026-08-27 14:25 UTCEPSS rescore
  34. 2026-08-26 22:22 UTCEG score recompute
  35. 2026-08-26 14:46 UTCEPSS rescore
  36. 2026-08-25 21:57 UTCEG score recompute
  37. 2026-08-25 13:49 UTCEPSS rescore
  38. 2026-08-24 21:36 UTCEG score recompute
  39. 2026-08-23 08:56 UTCEG score recompute
  40. 2026-08-23 00:19 UTCEPSS rescore
  41. 2026-08-22 08:37 UTCEG score recompute
  42. 2026-08-21 23:49 UTCEPSS rescore
  43. 2026-08-21 08:17 UTCEG score recompute
  44. 2026-08-20 22:55 UTCEPSS rescore
  45. 2026-08-19 19:47 UTCEG score recompute
  46. 2026-08-19 17:04 UTCEPSS rescore
  47. 2026-08-18 19:27 UTCEG score recompute
  48. 2026-08-18 13:48 UTCEPSS rescore
  49. 2026-08-17 19:07 UTCEG score recompute
  50. 2026-08-17 13:47 UTCEPSS rescore
  51. 2026-08-16 18:14 UTCEG score recompute
  52. 2026-08-16 14:56 UTCEPSS rescore
  53. 2026-08-16 06:03 UTCEG score recompute
  54. 2026-08-16 02:14 UTCEPSS rescore
  55. 2026-08-15 05:44 UTCEG score recompute
  56. 2026-08-15 01:30 UTCEPSS rescore
  57. 2026-08-14 16:25 UTCEG score recompute▲ 7.50
  58. 2026-08-14 16:24 UTCMITRE cvelistV5CVSS v3 → 7.5 · severity → HIGH
  59. 2026-08-13 22:25 UTCNVD update
  60. 2026-08-13 22:09 UTCEG score recompute
  61. 2026-08-13 22:09 UTCMITRE cvelistV5first tracked

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-56864?
CVE-2026-56864 is a high vulnerability published on August 13, 2026. A malicious GOSUMDB was capable of serving arbitrary module content not contained within the transparency log. This attack allows for a coordinating GOPROXY and GOSUMDB to serve a client malicious module content that cannot be detected by evaluating the transparency log. In order to determine if…
When was CVE-2026-56864 disclosed?
CVE-2026-56864 was first published in the National Vulnerability Database 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-2026-56864 actively exploited?
CVE-2026-56864 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 77.3% of all scored CVEs.
What is the CVSS score of CVE-2026-56864?
CVE-2026-56864 has a CVSS v3.1 base score of 7.5 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-56864?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-56864, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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