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HIGH

CVE-2026-59869

CVSS v3

7.5

HIGH

EPSS Score

0.6 %

exploit probability, as of 2026-10-17

CISA KEV

No

known exploited

Exploitation

—

SSVC status

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Affected and fixed versions

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • js-yamlnpmfrom 4.0.0 · fixed in 4.3.0

Vendor advisories

  • CVE-2026-59869 Red Hat Product Security710 products fixed · 60 known affected

    js-yaml: js-yaml: Denial of Service via crafted YAML documents

    grafana-infinity-datasource-npm as a component of Cryostat 4 · network-observability/network-observability-console-plugin-pf5-rhel9 as a component of Network Observability Operator · network-observability/network-observability-console-plugin-rhel9 as a component of Network Observability Operator

  • RHSA-2026:77316 Red Hat Product Security1 product fixed

    Red Hat Security Advisory: OpenShift Container Platform 4.12.100 bug fix and security update

  • RHSA-2026:77321 Red Hat Product Security1 product fixed

    Red Hat Security Advisory: OpenShift Container Platform 4.13.72 bug fix and security update

  • RHSA-2026:73853 Red Hat Product Security4 products fixed

    Red Hat Security Advisory: OpenShift Container Platform 4.16.72 bug fix and security update

  • RHSA-2026:73869 Red Hat Product Security4 products fixed

    Red Hat Security Advisory: OpenShift Container Platform 4.14.75 bug fix and security update

  • RHSA-2026:70587 Red Hat Product Security4 products fixed

    Red Hat Security Advisory: OpenShift Container Platform 4.17.58 bug fix and security update

98 more advisories

Full record on NVD

Description

js-yaml is a JavaScript YAML parser and dumper. From 3.0.0 before 3.15.0 and from 4.0.0 before 4.3.0, js-yaml can spend quadratic CPU time parsing a document whose size grows only linearly when a chain of mappings uses merge keys where each mapping merges the previous one. This issue is fixed in versions 3.15.0 and 4.3.0.

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published
2026-07-08
Last Modified
2026-07-08
GitHub Advisory
GHSA-52cp-r559-cp3m

Frequently asked questions

What is CVE-2026-59869?

js-yaml is a JavaScript YAML parser and dumper. From 3.0.0 before 3.15.0 and from 4.0.0 before 4.3.0, js-yaml can spend quadratic CPU time parsing a document whose size grows only linearly when a chain of mappings uses merge keys where each mapping merges the previous one. This issue is fixed in versions 3.15.0 and 4.3.0.

Is CVE-2026-59869 actively exploited?

Active exploitation of CVE-2026-59869 has not been confirmed. Its EPSS score was 0.6% on 2026-10-17, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-59869?

CVE-2026-59869 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

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