## Pillow: Arrow export leaks stale heap memory when PILLOW_ALIGNMENT > 1

- 種別: advisory
- 重大度: medium
- 関連技術: python
- CVE: CVE-2026-114501
- 公開日時: 2026-10-23T21:53:21.000Z
- 情報源: GitHub Advisory Database (https://github.com/advisories/GHSA-654x-cwwv-5j9c)
- パーマリンク: https://vulnpulse.app/items/ghsa-ghsa-654x-cwwv-5j9c

影響: pip:Pillow >= 11.2.1, < 13.0.0 → 13.0.0
When [PILLOW_ALIGNMENT](https://pillow.readthedocs.io/en/stable/reference/block_allocator.html#memory-pools) is set above 1, exporting an image to Arrow returns uninitialized heap memory mixed in with the pixel data. That memory can include pixels from images the process freed earlier. Details With an alignment above 1, the default allocator pads each row up to aligned_linesize and starts the first row at an aligned offset into the block. It then exports im->blocks[0].ptr as xsize ysize tightly…