Is js-yaml 3.14 vulnerable?
npm · 3 releases from 3.14.0 to 3.14.2 · latest js-yaml is 5.5.0 · checked 1 Nov 2026
Yes: 4 known advisories
Yes. js-yaml 3.14.2, the last 3.14 release, is affected by 4 known security advisories (3 high, 1 medium), including CVE-2026-84375, CVE-2026-59869, CVE-2026-53550. 1 more affects earlier 3.14.x releases. Upgrade to 3.15.2 or later to fix all of them.
npm install js-yaml@3.15.2Advisories affecting js-yaml 3.14.2
js-yaml: maxTotalMergeKeys does not limit CPU use for empty merge sources
- Affected
- >=4.0.0 <4.3.2 · >=3.0.0 <3.15.2
- Fixed in
- 3.15.2, 4.3.2
JS-YAML: Quadratic CPU consumption in !!omap resolution (3.x and 4.x) — CVE-2026-59870 fix not backported
- Affected
- >=4.0.0 <4.3.1 · >=3.0.0 <3.15.1
- Fixed in
- 3.15.1, 4.3.1
js-yaml: YAML merge-key chains can force quadratic CPU consumption
- Affected
- >=3.0.0 <3.15.0 · >=4.0.0 <4.3.0
- Fixed in
- 3.15.0, 4.3.0
JS-YAML: Quadratic-complexity DoS in merge key handling via repeated aliases
- Affected
- >=4.0.0 <4.2.0 · <3.15.0
- Fixed in
- 3.15.0, 4.2.0
Fixed within 3.14.x, affecting earlier releases
js-yaml has prototype pollution in merge (<<)
- Affected
- >=4.0.0 <4.1.1 · <3.14.2
- Fixed in
- 3.14.2, 4.1.1
Which of your client projects are still on js-yaml 3.14?
NPMscan reads the lockfiles in every GitHub repo you pick, finds the exact js-yaml version each one installs, and checks it against these advisories. Each finding comes with the command that fixes it.
Other js-yaml versions
Advisory data from OSV.dev (opens OSV.dev in a new tab), which includes the GitHub Advisory Database. Release list from the npm registry. Refreshed daily.