CVE-2026-59200
Pillow is a Python imaging library. From 5.1.0 until 12.3.0, PdfParser.PdfStream.decode() in PIL/PdfParser.py calls zlib.decompress() with bufsize set to the PDF stream Length field without bounding the decompressed output size, allowing a crafted FlateDecode PDF stream to exhaust memory from a small file. This issue is fixed in version 12.3.0.
Weakness
Pillow is a Python imaging library. From 5.1.0 until 12.3.0, PdfParser.PdfStream.decode() in PIL/PdfParser.py calls zlib.decompress() with bufsize set to the PDF stream Length field without bounding the decompressed output size, allowing a crafted FlateDecode PDF stream to exhaust memory from a small file. This issue is fixed in version 12.3.0.
Affected products
- python pillow
References
- https://github.com/python-pillow/Pillow/commit/f7a31ea75e460e108c37126da1f47812f21f6b09
- https://github.com/python-pillow/Pillow/pull/9718
- https://github.com/python-pillow/Pillow/releases/tag/12.3.0
- https://github.com/python-pillow/Pillow/security/advisories/GHSA-jjj6-mw9f-p565
- https://github.com/python-pillow/Pillow/security/advisories/GHSA-jjj6-mw9f-p565
Find the bug before an attacker does.
Sign in with GitHub and run your first audit in under a minute. The free plan needs no credit card.