CVE-2026-12151

HIGHPre-NVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.5 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.6%, top 55% 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, secondary
Trending — Patch released this week
7.5
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 1%CVSS: 7.5Exploit: NoneExposed: 0

A fix is available — apply it.

Impact: The undici WebSocket client enforces maxPayloadSize on the cumulative byte count of fragments in a message but does not enforce a limit on the number of fragments. A malicious WebSocket server can stream many small or empty continuation frames that each pass per-frame and cumulative-size validation, collectively causing unbounded memory growth in the client process. The result is memory exhaustion and a denial of service.

Affected applications are those using the undici WebSocket client (new WebSocket(...)) or the WebSocketStream API that can be induced to connect to an attacker-controlled or compromised WebSocket endpoint.

All releases starting at undici 6.17.0 are affected.

Patches: Upgrade to undici >= 6.26.0, >= 7.28.0, or >= 8.5.0. Workarounds: No workaround is available. The fix must be applied through an upgrade.

CVSS v3
7.5
EG Score
7.5(medium)
EPSS
45.0%
KEV
Not listed

Published

June 17, 2026

Last Modified

July 6, 2026

Advisory Details (2)

Auto-updated Jun 17, 2026
Patch available. Sources: github.
github Patch Available

undici WebSocket client vulnerable to denial of service via fragment count bypass · Advisory · nodejs/undici · GitHub

https://github.com/nodejs/undici/security/advisories/GHSA-vxpw-j846-p89q
generic

Security Advisories | OpenJS Foundation CVE Numbering Authority

https://cna.openjsf.org/security-advisories.html

Vendor Advisories for CVE-2026-12151(3)

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

Patch Availability(3)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatnodejs24-1:24.18.0-1.el10_22026-07-06redhat
redhatnodejs22-1:22.23.1-2.el10_22026-07-06redhat
redhatcluster-observability-operator/troubleshooting-panel-console-plugin-rhel9:17828394942026-07-01redhat

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

(1 across 1 ecosystem)
npm(1)
PackageVulnerable rangeFixed inDependents
undici—8.5.0—

Weakness Classification(2)

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

Additional Vendor Advisories

(1)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 30× in last 7d / 70× 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. 2026-07-06 21:48 UTCEG score recompute
  2. 2026-07-06 21:48 UTCVendor advisory
  3. 2026-07-06 16:27 UTCEPSS rescore
  4. 2026-07-06 06:36 UTCEG score recompute
  5. 2026-07-06 06:36 UTCVendor advisory
  6. 2026-07-06 02:23 UTCEPSS rescore
  7. 2026-07-05 17:36 UTCEG score recompute
  8. 2026-07-05 17:36 UTCVendor advisory
  9. 2026-07-05 04:35 UTCEG score recompute
  10. 2026-07-05 04:35 UTCVendor advisory
  11. 2026-07-05 02:30 UTCEPSS rescore
  12. 2026-07-05 02:30 UTCEPSS rescore
  13. 2026-07-04 15:22 UTCEG score recompute
  14. 2026-07-04 15:22 UTCVendor advisory
  15. 2026-07-04 06:31 UTCEPSS rescore
  16. 2026-07-04 02:11 UTCEG score recompute
  17. 2026-07-04 02:11 UTCVendor advisory
  18. 2026-07-03 13:10 UTCEG score recompute
  19. 2026-07-03 13:10 UTCVendor advisory
  20. 2026-07-03 00:09 UTCEG score recompute
  21. 2026-07-03 00:09 UTCVendor advisory
  22. 2026-07-02 11:09 UTCEG score recompute
  23. 2026-07-02 11:09 UTCVendor advisory
  24. 2026-07-01 21:39 UTCEG score recompute
  25. 2026-07-01 15:06 UTCEPSS rescore
Show 45 more
  1. 2026-07-01 15:06 UTCEPSS rescore
  2. 2026-07-01 08:39 UTCEG score recompute
  3. 2026-06-30 23:22 UTCEPSS rescore
  4. 2026-06-30 19:39 UTCEG score recompute
  5. 2026-06-30 06:39 UTCEG score recompute
  6. 2026-06-29 17:37 UTCEG score recompute
  7. 2026-06-29 14:06 UTCEPSS rescore
  8. 2026-06-29 04:36 UTCEG score recompute
  9. 2026-06-28 15:34 UTCEG score recompute
  10. 2026-06-28 14:07 UTCEPSS rescore
  11. 2026-06-28 04:56 UTCEPSS rescore
  12. 2026-06-28 04:56 UTCEPSS rescore
  13. 2026-06-28 02:34 UTCEG score recompute
  14. 2026-06-27 13:33 UTCEG score recompute
  15. 2026-06-27 03:08 UTCEPSS rescore
  16. 2026-06-27 00:32 UTCEG score recompute
  17. 2026-06-26 11:30 UTCEG score recompute
  18. 2026-06-25 21:32 UTCEG score recompute
  19. 2026-06-25 13:49 UTCEPSS rescore
  20. 2026-06-25 08:32 UTCEG score recompute
  21. 2026-06-24 19:31 UTCEG score recompute
  22. 2026-06-24 14:05 UTCEPSS rescore
  23. 2026-06-24 06:18 UTCEG score recompute
  24. 2026-06-23 21:32 UTCEPSS rescore
  25. 2026-06-23 17:16 UTCEG score recompute
  26. 2026-06-23 04:14 UTCEG score recompute
  27. 2026-06-22 15:13 UTCEG score recompute
  28. 2026-06-22 14:25 UTCEPSS rescore
  29. 2026-06-22 14:25 UTCEPSS rescore
  30. 2026-06-22 02:11 UTCEG score recompute
  31. 2026-06-21 14:56 UTCEPSS rescore
  32. 2026-06-21 14:56 UTCEPSS rescore
  33. 2026-06-21 13:08 UTCEG score recompute
  34. 2026-06-21 01:59 UTCEPSS rescore
  35. 2026-06-21 01:59 UTCEPSS rescore
  36. 2026-06-21 00:04 UTCEG score recompute
  37. 2026-06-20 11:00 UTCEG score recompute
  38. 2026-06-19 21:59 UTCEG score recompute
  39. 2026-06-19 19:25 UTCEPSS rescore
  40. 2026-06-19 08:59 UTCEG score recompute
  41. 2026-06-18 19:59 UTCEG score recompute
  42. 2026-06-18 17:52 UTCEPSS rescore
  43. 2026-06-18 06:57 UTCEG score recompute
  44. 2026-06-17 17:53 UTCEG score recompute
  45. 2026-06-17 17:52 UTCNVD updatefirst tracked

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-12151?
CVE-2026-12151 is a high vulnerability published on June 17, 2026. Impact: The undici WebSocket client enforces maxPayloadSize on the cumulative byte count of fragments in a message but does not enforce a limit on the number of fragments. A malicious WebSocket server can stream many small or empty continuation frames that each pass per-frame and cumulative-size…
When was CVE-2026-12151 disclosed?
CVE-2026-12151 was first published in the National Vulnerability Database on June 17, 2026, with the most recent update on July 6, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-12151 actively exploited?
CVE-2026-12151 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 45.0% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-12151?
CVE-2026-12151 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-12151?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-12151, 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-2026-12151

Explore →

Is Your Infrastructure Affected by CVE-2026-12151?

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

Start Free Scan →Browse All CVEs