CVE-2026-59870

HIGHNVD 7.57.5
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to NVD's CVSS score.

This high-severity CVE scores 7.5 under NVD CVSS v3. EPSS exploit probability: 0.7% (54th percentile of EPSS-scored CVEs). GitHub Security Advisory CVSS 5.3 is lower than this score; a lower GitHub score revises it only when its advisory is newer than the CVE record's last change, and this advisory (published 2026-07-20) is not newer than that change (2026-10-25), so it does not.

Triggered by: Headline CVSS from NVD CVSS v3
Sources: EPSS, GitHub Security Advisory, NVD CVSS v3
Trending — 4 sources updated this weekElevated

Also known asEUVD-2026-42300 (ENISA EUVD) · GHSA-724g-mxrg-4qvm (GitHub Security Advisories)Source: ENISA EUVD

7.5EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • CISA's Vulnrichment rates exploitation as PoC; EchelonGraph holds no exploit-code reference for it
CISA-KEV: Not listedEPSS PROB: 0.7%CVSS: 7.5Exploit: No code on recordExposed services: Not assessed

A fix is available — apply it.

js-yaml is a JavaScript YAML parser and dumper. Prior to 3.15.1, 4.3.1, and 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. In v3 and v4, !!omap is active and exploitable by default. v5 doesn't use !!omap by default, and the chances of activating it are very low.This issue is fixed in 3.15.1, 4.3.1, and 5.2.1.

CVSS v3
7.5
EG Score
7.5HIGHmedium confidence
EG Risk
65
EG Risk 65/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity75% × 45%
Impact severity (EG Severity): CVSS 7.5 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation40% × 40%
EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Attend at high (mission-essential systems).
Exploitation public PoC (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
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
0.7%
EPSS %ILE
54th
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (7.5): severity, escalated by confirmed exploitation. This CVE's 7.5 is its impact severity (EG Severity), not escalated.

EG Severity
7.5 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.NVD CVSS v3 · CVSS v3.0 or v3.1
EG Likelihood
0.7% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-01). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track at medium mission impactTrack at low or medium mission impact; Attend at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; 60 days if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track 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 public PoC (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; 60 days if it is not.

The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

July 8, 2026

Last Modified

October 25, 2026

Advisory Details (2)

Auto-updated Jul 8, 2026
Patch available. Sources: github_commit, github.
GitHub advisoryMentions a patch (unverified)

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

Patch Availability(9)

Vendor / EcosystemFix (by version range) / 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
npmjs-yaml @ 5.2.1 (fixes >= 5.0.0, <= 5.2.0)—ghsa

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 rangeFix by version rangeDependents
js-yaml—
  • 5.0.0 up to 5.2.1: fixed in 5.2.1
—

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 12× in last 7d / 48× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. 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. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

Showing the most recent 100 of 268 refreshes on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 168 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-01 18:17 UTCEG score recompute
  2. 2026-11-01 18:17 UTCVendor advisory
  3. 2026-11-01 18:17 UTCGHSA enrichmentGHSA-724g-mxrg-4qvm · GitHub severity MODERATE · GitHub CVSS 5.3
  4. 2026-11-01 16:35 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  5. 2026-11-01 07:42 UTCGHSA enrichmentGHSA-724g-mxrg-4qvm · GitHub severity MODERATE · GitHub CVSS 5.3
  6. 2026-11-01 07:42 UTCEG score recompute
  7. 2026-10-31 16:33 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  8. 2026-10-30 16:34 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  9. 2026-10-29 16:33 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  10. 2026-10-28 16:32 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  11. 2026-10-27 16:32 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  12. 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  13. 2026-10-25 20:26 UTCEG score recompute
  14. 2026-10-25 20:26 UTCVendor advisory
  15. 2026-10-25 16:33 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  16. 2026-10-25 14:16 UTCEG score recompute
  17. 2026-10-24 16:33 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  18. 2026-10-23 16:32 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  19. 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  20. 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  21. 2026-10-20 18:57 UTCEG score recompute
  22. 2026-10-20 18:57 UTCVendor advisory
  23. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  24. 2026-10-19 16:32 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  25. 2026-10-18 03:27 UTCEG score recompute
Show 75 more
  1. 2026-10-17 16:35 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  2. 2026-10-16 16:43 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  3. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  4. 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  5. 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  6. 2026-10-13 15:48 UTCEG score recompute
  7. 2026-10-13 15:48 UTCVendor advisory
  8. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  9. 2026-10-12 15:52 UTCEG score recompute
  10. 2026-10-11 19:36 UTCEG score recompute
  11. 2026-10-11 16:51 UTCEG score recompute
  12. 2026-10-11 14:13 UTCEG score recompute
  13. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  14. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  15. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  16. 2026-10-08 17:13 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  17. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  18. 2026-10-06 16:21 UTCVendor advisory
  19. 2026-10-06 15:38 UTCEG score recompute
  20. 2026-10-06 15:38 UTCVendor advisory
  21. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  22. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  23. 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  24. 2026-10-02 17:56 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  25. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  26. 2026-10-01 16:12 UTCEG score recompute
  27. 2026-10-01 16:12 UTCVendor advisory
  28. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  29. 2026-09-29 15:22 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  30. 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  31. 2026-09-28 13:23 UTCEG score recompute
  32. 2026-09-28 13:23 UTCVendor advisory
  33. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  34. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  35. 2026-09-24 14:04 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  36. 2026-09-24 11:52 UTCEG score recompute
  37. 2026-09-24 11:52 UTCVendor advisory
  38. 2026-09-23 17:54 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  39. 2026-09-23 06:11 UTCEG score recompute
  40. 2026-09-23 06:11 UTCVendor advisory
  41. 2026-09-20 20:16 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  42. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  43. 2026-09-18 05:45 UTCEG score recompute
  44. 2026-09-18 05:45 UTCVendor advisory
  45. 2026-09-17 19:31 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  46. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  47. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  48. 2026-09-15 03:11 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  49. 2026-09-13 23:50 UTCEG score recompute
  50. 2026-09-13 23:50 UTCVendor advisory
  51. 2026-09-13 16:47 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  52. 2026-09-13 08:25 UTCVendor advisory
  53. 2026-09-12 16:42 UTCEG score recompute
  54. 2026-09-12 16:42 UTCVendor advisory
  55. 2026-09-12 03:35 UTCEG score recompute
  56. 2026-09-12 03:35 UTCVendor advisory
  57. 2026-09-11 14:53 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  58. 2026-09-10 09:35 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  59. 2026-09-08 22:01 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  60. 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  61. 2026-09-06 14:04 UTCEG score recompute
  62. 2026-09-06 14:04 UTCVendor advisory
  63. 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  64. 2026-09-05 22:49 UTCEG score recompute
  65. 2026-09-05 22:49 UTCVendor advisory
  66. 2026-09-04 05:07 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  67. 2026-09-02 14:12 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  68. 2026-09-01 13:54 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  69. 2026-09-01 04:40 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  70. 2026-08-30 20:25 UTCEG score recompute
  71. 2026-08-30 20:25 UTCVendor advisory
  72. 2026-08-30 19:17 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  73. 2026-08-30 07:37 UTCEG score recompute
  74. 2026-08-30 07:37 UTCVendor advisory
  75. 2026-08-30 01:22 UTCEPSS rescoreEPSS 0.6% · 48th percentile

Frequently asked(5)

What is CVE-2026-59870?
CVE-2026-59870 is a high-severity vulnerability; its CVE record was published on July 8, 2026. js-yaml is a JavaScript YAML parser and dumper. Prior to 3.15.1, 4.3.1, and 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 the CVE record for CVE-2026-59870 published?
The CVE record for CVE-2026-59870 was published on July 8, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of October 25, 2026; the record at its source may have been updated since.
Is CVE-2026-59870 actively exploited?
CVE-2026-59870 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.7% probability of exploitation in the next 30 days (54th percentile of EPSS-scored CVEs).
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?
A fix for CVE-2026-59870 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-59870 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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