CVE-2026-59870

HIGHNVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.5 under NVD CVSS v3. EPSS exploit probability: 0.4%, top 72% 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
Elevated
7.5
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 7.5Exploit: NoneExposed: 0

A fix is available — apply it.

js-yaml is a JavaScript YAML parser and dumper. From 5.0.0 before 5.2.1, YAML11_SCHEMA support for the !!omap tag in src/tag/sequence/omap.ts uses omapTag.addItem() to perform a linear duplicate-key scan on every insertion, causing O(n^2) CPU consumption when yaml.load() parses a crafted ordered-map document. This issue is fixed in version 5.2.1.

CVSS v3
7.5
EG Score
7.5(medium)
EPSS
28.3%
KEV
Not listed

Published

July 8, 2026

Last Modified

July 10, 2026

Advisory Details (2)

Auto-updated Jul 8, 2026
🔬 Proof of concept available. Patch available. Sources: github_commit, github.
github Patch Available🟡 PoC Available

Quadratic-complexity (O(n^2)) DoS in js-yaml 5.x via !!omap tag in YAML11_SCHEMA · Advisory · nodeca/js-yaml · GitHub

https://github.com/nodeca/js-yaml/security/advisories/GHSA-724g-mxrg-4qvm
github_commit

commit 39f3211a2f01 (nodeca/js-yaml)

Fix landed in nodeca/js-yaml commit 39f3211a2f01 — awaiting tagged release

https://github.com/nodeca/js-yaml/commit/39f3211a2f01b3c6982710cf21434ab7060acefe

Vendor Advisories for CVE-2026-59870(9)

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

Patch Availability(8)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatnodejs22-main-22.23.1-2.hum12026-07-03redhat
redhatrust-main-1.96.1-1.hum12026-07-02redhat
redhatnodejs24-main-24.18.0-0.2.hum12026-07-01redhat
redhatnodejs26-main-26.4.0-1.3.hum12026-06-30redhat
redhatdotnet8-0-main-8.0.128-1.hum12026-06-18redhat
redhatnodejs20-main-20.20.2-1.hum12026-04-21redhat
redhatyarnpkg-main-1.22.22-18.1.hum12026-04-11redhat
redhatnodejs25-main-25.9.0-1.1.hum12026-04-10redhat

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
js-yaml—5.2.1—

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 11× in last 7d / 37× 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. 2026-07-22 14:08 UTCEPSS rescore
  2. 2026-07-22 14:08 UTCEPSS rescore
  3. 2026-07-21 15:25 UTCEPSS rescore
  4. 2026-07-21 15:25 UTCEPSS rescore
  5. 2026-07-20 17:08 UTCEPSS rescore
  6. 2026-07-19 14:31 UTCEPSS rescore
  7. 2026-07-19 02:29 UTCEPSS rescore
  8. 2026-07-18 10:04 UTCEPSS rescore
  9. 2026-07-16 23:32 UTCVendor advisory
  10. 2026-07-16 17:03 UTCEPSS rescore
  11. 2026-07-16 10:45 UTCVendor advisory
  12. 2026-07-15 21:57 UTCVendor advisory
  13. 2026-07-15 16:57 UTCEPSS rescore
  14. 2026-07-15 16:57 UTCEPSS rescore
  15. 2026-07-15 09:08 UTCVendor advisory
  16. 2026-07-15 02:00 UTCEPSS rescore
  17. 2026-07-15 02:00 UTCEPSS rescore
  18. 2026-07-14 20:18 UTCVendor advisory
  19. 2026-07-14 07:29 UTCVendor advisory
  20. 2026-07-13 22:31 UTCEPSS rescore
  21. 2026-07-13 18:39 UTCVendor advisory
  22. 2026-07-13 06:13 UTCEPSS rescore
  23. 2026-07-13 06:13 UTCEPSS rescore
  24. 2026-07-13 05:51 UTCVendor advisory
  25. 2026-07-12 17:02 UTCVendor advisory
Show 12 more
  1. 2026-07-12 05:46 UTCEPSS rescore
  2. 2026-07-12 04:14 UTCVendor advisory
  3. 2026-07-11 15:26 UTCEG score recompute▲ 2.20
  4. 2026-07-11 15:26 UTCVendor advisory
  5. 2026-07-11 08:27 UTCEPSS rescore
  6. 2026-07-11 08:27 UTCEPSS rescore
  7. 2026-07-10 20:19 UTCNVD updateCVSS v3 → 7.5 · severity → HIGH
  8. 2026-07-10 15:33 UTCVendor advisory
  9. 2026-07-09 19:10 UTCEPSS rescore
  10. 2026-07-09 19:10 UTCEPSS rescore
  11. 2026-07-08 15:46 UTCEG score recompute
  12. 2026-07-08 15:45 UTCMITRE cvelistV5first tracked

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-59870?
CVE-2026-59870 is a high vulnerability published on July 8, 2026. js-yaml is a JavaScript YAML parser and dumper. From 5.0.0 before 5.2.1, YAML11_SCHEMA support for the !!omap tag in src/tag/sequence/omap.ts uses omapTag.addItem() to perform a linear duplicate-key scan on every insertion, causing O(n^2) CPU consumption when yaml.load() parses a crafted…
When was CVE-2026-59870 disclosed?
CVE-2026-59870 was first published in the National Vulnerability Database on July 8, 2026, with the most recent update on July 10, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-59870 actively exploited?
CVE-2026-59870 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 28.3% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-59870?
CVE-2026-59870 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-59870?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-59870, 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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