Sourced from js-yaml's changelog.

4.3.1 - 2026-07-31

Security

• [backport] Remove quadratic complexity from !!omap duplicate key detection.

4.3.0 - 2026-06-27

Added

• [backport] Added maxTotalMergeKeys (10000) loader option to limit the total number of keys processed by YAML merge (<<) across one load() / loadAll() call.

Fixed

• Restore umd builds back to es5.

Removed

• [backport] maxMergeSeqLength replaced with maxTotalMergeKeys for limiting YAML merge processing.

[4.2.0] - 2026-06-01

Added

• Added docs/safety.md with notes about processing untrusted YAML.
• Added maxDepth (100) loader option. Not a problem, but gives a better exception instead of RangeError on stack overflow.
• Added maxMergeSeqLength (20) loader option. Not a problem after merge fix, but an additional restriction for safety.
• Added sourcemaps to dist/ builds.

Changed

• Stop resolving numbers with underscores as numeric scalars, #627.
• Switched dev toolchains to Vite / neostandard.
• Updated demo.
• Reorganized tests.
• dist/ files are no longer kept in the repository.

Fixed

• Fix parsing of properties on the first implicit block mapping key, #62.
• Fix trailing whitespace handling when folding flow scalar lines, #307.
• Reject top-level block scalars without content indentation, #280.
• Ensure numbers survive round-trip, #737.
• Fix test coverage for issue #221.
• Fix flow scalar trailing whitespace folding, #307.
• Fix digits in YAML named tag handles.

Security

• Fix potential DoS via quadratic complexity in merge - deduplicate repeated elements (makes sense for malformed files > 10K).

[3.14.2] - 2025-11-15

Security

... (truncated)

• 86e91b8 4.3.1 released
• c3cc4b0 Backport quadratic complexity fix for !!omap
• 33d05b5 4.3.0 released
• 663bfab Drop demo publish, to not override new v5 one.
• 1cb8c7b Add v4-legacy tag for publish
• 02f27af Restore umd builds back to es5
• 8be84ed Fix es5 compatibility
• 59423c6 Replace maxMergeSeqLength option with maxTotalMergeKeys (more robust). Ba...
• 6842ef6 doc polish
• 590dbab 4.2.0 released
• Additional commits viewable in compare view

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