CVE-2026-64643

MEDIUMNVD 5.35.3—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 5.3 under NVD CVSS v3. EPSS exploit probability: 0.5%, top 58% 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: epss, nvd
5.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 5.3Exploit: None knownExposed: 0

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

Next.js is a React framework for building full-stack web applications. In versions 12.0.0 through 15.5.20 and 16.0.0 through 16.2.10, Next.js applications using App Router, Server Actions (use server) or use cache endpoints can be disclosed bypassing any authentication on the pages where these endpoints are usually used. Server Action IDs can be disclosed to unauthenticated users via publicly served client artifacts (for example, static chunks containing action references). Affected users are applications using App Router and Server Actions. By itself, this disclosure is typically a recon/enumeration primitive; however, it can increase risk when combined with other weaknesses. This issue has been fixed in versions 15.5.21 and 16.2.11.

CVSS v3
5.3
EG Score
5.3(medium)
EG Risk
39(Track)
EG Risk 39/100SSVC: 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
Severity53% × 45%
Exploitation1% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
42%
KEV
Not listed

Published

July 22, 2026

Last Modified

July 29, 2026

Advisory Details (5)

Auto-updated Jul 27, 2026
Patch available. Sources: github_commit, github_release, github.
github Patch Available

Unauthenticated disclosure of internal Server Function endpoints · Advisory · vercel/next.js · GitHub

https://github.com/vercel/next.js/security/advisories/GHSA-955p-x3mx-jcvp
github_release Patch Available

v16.2.11

Patch available: vercel/next.js v16.2.11

https://github.com/vercel/next.js/releases/tag/v16.2.11
github_release Patch Available

v15.5.21

Patch available: vercel/next.js v15.5.21

https://github.com/vercel/next.js/releases/tag/v15.5.21
github_commit Patch Available

commit ff12a6124e15 (vercel/next.js)

Patch available: vercel/next.js v15.5.21 (contains commit ff12a6124e15)

https://github.com/vercel/next.js/commit/ff12a6124e1504f17b62de948b8a553fdecaef7b
github_commit Patch Available

commit 1b0c3ae912a3 (vercel/next.js)

Patch available: vercel/next.js v16.2.11 (contains commit 1b0c3ae912a3)

https://github.com/vercel/next.js/commit/1b0c3ae912a3ad925c60065cc8d55b070fa8bcd3

Vendor Advisories for CVE-2026-64643(1)

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

Affected Packages

(1 across 1 ecosystem)
npm(1)
PackageVulnerable rangeFixed inDependents
next—16.2.11—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 7× in last 7d / 42× 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. 2026-09-14 05:32 UTCEG score recompute
  2. 2026-09-13 03:11 UTCEG score recompute
  3. 2026-09-12 00:50 UTCEG score recompute
  4. 2026-09-11 14:53 UTCEPSS rescore
  5. 2026-09-11 09:37 UTCEPSS rescore
  6. 2026-09-10 21:14 UTCEG score recompute
  7. 2026-09-09 09:10 UTCEG score recompute
  8. 2026-09-08 22:01 UTCEPSS rescore
  9. 2026-09-07 21:39 UTCEG score recompute
  10. 2026-09-07 16:01 UTCEPSS rescore
  11. 2026-09-06 13:47 UTCEPSS rescore
  12. 2026-09-05 19:33 UTCEG score recompute
  13. 2026-09-05 15:31 UTCEPSS rescore
  14. 2026-09-04 13:39 UTCEG score recompute
  15. 2026-09-04 05:07 UTCEPSS rescore
  16. 2026-09-02 14:12 UTCEPSS rescore
  17. 2026-09-01 23:30 UTCEG score recompute
  18. 2026-09-01 13:54 UTCEPSS rescore
  19. 2026-09-01 04:40 UTCEPSS rescore
  20. 2026-08-31 03:10 UTCEG score recompute
  21. 2026-08-30 19:17 UTCEPSS rescore
  22. 2026-08-30 01:22 UTCEPSS rescore
  23. 2026-08-30 00:48 UTCEG score recompute
  24. 2026-08-28 21:42 UTCEPSS rescore
  25. 2026-08-27 04:47 UTCEG score recompute
Show 59 more
  1. 2026-08-26 14:47 UTCEPSS rescore
  2. 2026-08-26 02:16 UTCEG score recompute
  3. 2026-08-25 13:49 UTCEPSS rescore
  4. 2026-08-24 23:55 UTCEG score recompute
  5. 2026-08-23 21:34 UTCEG score recompute
  6. 2026-08-23 00:19 UTCEPSS rescore
  7. 2026-08-22 19:14 UTCEG score recompute
  8. 2026-08-21 23:49 UTCEPSS rescore
  9. 2026-08-21 16:54 UTCEG score recompute
  10. 2026-08-20 22:55 UTCEPSS rescore
  11. 2026-08-20 14:30 UTCEG score recompute
  12. 2026-08-19 17:04 UTCEPSS rescore
  13. 2026-08-19 11:44 UTCEG score recompute
  14. 2026-08-18 13:48 UTCEPSS rescore
  15. 2026-08-18 09:14 UTCEG score recompute
  16. 2026-08-17 13:47 UTCEPSS rescore
  17. 2026-08-17 06:48 UTCEG score recompute
  18. 2026-08-16 14:56 UTCEPSS rescore
  19. 2026-08-16 04:28 UTCEG score recompute
  20. 2026-08-15 02:07 UTCEG score recompute
  21. 2026-08-15 01:30 UTCEPSS rescore
  22. 2026-08-13 23:47 UTCEG score recompute
  23. 2026-08-13 22:00 UTCEPSS rescore
  24. 2026-08-12 21:27 UTCEG score recompute
  25. 2026-08-12 13:51 UTCEPSS rescore
  26. 2026-08-11 19:07 UTCEG score recompute
  27. 2026-08-11 00:00 UTCEPSS rescore
  28. 2026-08-09 14:25 UTCEG score recompute
  29. 2026-08-09 13:47 UTCEPSS rescore
  30. 2026-08-08 16:37 UTCEPSS rescore
  31. 2026-08-08 12:05 UTCEG score recompute
  32. 2026-08-07 09:44 UTCEG score recompute
  33. 2026-08-06 13:47 UTCEPSS rescore
  34. 2026-08-06 07:24 UTCEG score recompute
  35. 2026-08-05 19:17 UTCEPSS rescore
  36. 2026-08-05 19:17 UTCEPSS rescore
  37. 2026-08-05 05:04 UTCEG score recompute
  38. 2026-08-04 15:10 UTCEPSS rescore
  39. 2026-08-04 10:39 UTCEPSS rescore
  40. 2026-08-04 02:34 UTCEG score recompute
  41. 2026-08-03 10:36 UTCEPSS rescore
  42. 2026-08-03 00:14 UTCEG score recompute
  43. 2026-08-02 02:27 UTCEPSS rescore
  44. 2026-08-01 21:53 UTCEG score recompute
  45. 2026-08-01 04:16 UTCEPSS rescore
  46. 2026-07-30 17:02 UTCEG score recompute
  47. 2026-07-30 16:28 UTCEPSS rescore
  48. 2026-07-30 01:30 UTCEPSS rescore
  49. 2026-07-30 01:30 UTCEPSS rescore
  50. 2026-07-29 14:39 UTCEG score recompute▼ 1.00
  51. 2026-07-29 14:39 UTCNVD updateCVSS v3 → 5.3
  52. 2026-07-28 16:31 UTCEG score recompute
  53. 2026-07-28 15:37 UTCEPSS rescore
  54. 2026-07-27 19:33 UTCEG score recompute
  55. 2026-07-27 18:22 UTCEG score recompute
  56. 2026-07-27 18:11 UTCEG score recompute▲ 6.30
  57. 2026-07-27 18:09 UTCMITRE cvelistV5CVSS v3 → 6.3 · CVSS v4 → 6.3
  58. 2026-07-23 03:22 UTCEG score recompute
  59. 2026-07-22 23:22 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-64643?
CVE-2026-64643 is a medium vulnerability published on July 22, 2026. Next.js is a React framework for building full-stack web applications. In versions 12.0.0 through 15.5.20 and 16.0.0 through 16.2.10, Next.js applications using App Router, Server Actions (use server) or use cache endpoints can be disclosed bypassing any authentication on the pages where these…
When was CVE-2026-64643 disclosed?
CVE-2026-64643 was first published in the National Vulnerability Database on July 22, 2026, with the most recent update on July 29, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-64643 actively exploited?
CVE-2026-64643 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 57.6% of all scored CVEs.
What is the CVSS score of CVE-2026-64643?
CVE-2026-64643 has a CVSS v3 base score of 5.3 (NVD).
How do I remediate CVE-2026-64643?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-64643, 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

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-64643

Explore →

Is Your Infrastructure Affected by CVE-2026-64643?

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

Start Free Scan →Browse All CVEs