js-yaml

5.5.0 · 15 Oct 2026MIT322.7M / weekRepository Homepage npm Atom feed

Same major only

1 release in betweenevery note read

Other targets from 5.2.0Newest 5.x, Latest5.5.0 Clears its 3 advisories5.4.1

0
changes to make: 1
advisory fixed: 1
new: 0
fixes

Security

2 advisories still affect 5.2.1

js-yaml: Exponential parsing time in flow collections leads to denial of servicehigh · GHSA-pm4m-ph32-ghv5
js-yaml: maxTotalMergeKeys does not limit CPU use for empty merge sourcesmoderate · GHSA-r3ph-w7gj-g6xm

Upgrading to 5.4.1 clears them.

Fixes 1 advisory affecting 5.2.0

js-yaml: Quadratic-complexity (O(n^2)) DoS via !!omap tag in YAML11_SCHEMAmoderate · GHSA-724g-mxrg-4qvm

Remove quadratic complexity from !!omap addItem. Regression from v5 (usually not critical, because YAML11_SCHEMA is not default anymore).
5.2.1

Release by release

5.2.1
2 Jul 20261 new
- new
  Add Map support to !!omap (should work when realMapTag used)

Upgrade to 5.2.1

npm install js-yaml@5.2.1

What 5.2.1 needs

Reading 5.2.1's manifest…

Check against your package.json

Which of your other dependencies stand in the way of 5.2.1. Read once, not stored.

After upgrading

Run the type checker, the linter and the tests.
Build, and look for new deprecation warnings.
Update peer dependencies the new version asks for.
2 advisories still affect 5.2.1.