# PostCSS 8.5.17

- Product: PostCSS (https://whatsnew.fyi/product/postcss)
- Vendor: PostCSS
- Date: 2026-07-11
- Version: 8.5.17
- Original notes: https://github.com/postcss/postcss/releases/tag/8.5.17
- Permalink: https://whatsnew.fyi/product/postcss/releases/8.5.17

What's New is an index, not a publisher: every entry below links to the vendor's own release notes, which are the authoritative source. Entries are labelled where they are hand-curated sample data, pre-releases, or drawn from a secondary source such as a developer blog.

Reuse: the summaries, labels and curation here are © What's New. Quote freely with attribution and a link back; wholesale republication of the corpus is not permitted — terms: https://whatsnew.fyi/terms. The vendors' own release notes remain their publishers'.

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- **fixed** — Fixed Maximum call stack size exceeded error
- **security** — Fixed Prototype hijacking for postcss.fromJSON()
- **fixed** — Fixed Input#origin() for unmapped end position

- Fixed `Maximum call stack size exceeded` error.
- Fixed Prototype hijacking for `postcss.fromJSON()`.
- Fixed `Input#origin()` for unmapped end position (by @chatman-media).