CVE-2026-112394 Pillow: P;2L and P;4L decoders may read 1 to 3 bytes past the passed buffer size

What is CVE-2026-112394?

CVE-2026-112394 is a medium-severity vulnerability in Python Pillow, published on 19 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Pillow is a Python imaging library. Prior to 13.0.0, Pillow's P;2L and P;4L raw decoders can read past the end of an input buffer. ImagingRawDecode calculates a packed-pixel row size, while the unpackers read separately padded bit planes. A caller can supply a buffer and image dimensions whose accepted size is smaller than the unpacker's actual footprint. This can disclose up to three adjacent heap bytes in output pixels or crash the process. This issue is fixed in version 13.0.0.

Weakness: CWE-126

Which versions are affected by CVE-2026-112394?

4 open source packages ship an affected version, including pillow and Pillow. It affects 1 product.

Products include Python Pillow.

How do I fix CVE-2026-112394?

Upgrade pillow to 13.0.0 or later.

Is CVE-2026-112394 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-112394 exists.

Other vulnerabilities in Python Pillow

• CVE-2014-3007 Pillow command injection Critical 10.0
• CVE-2026-96639 Pillow multi-frame loaders can reuse stale native image storage after mode transitions Critical 9.8
• CVE-2022-30595 Buffer over-flow in Pillow Critical 9.8
• CVE-2021-25289 Out of bounds write in Pillow Critical 9.8
• CVE-2016-4009 Pillow Integer overflow in ImagingResampleHorizontal Critical 9.8

All Python Pillow vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BIT-pillow-2026-112394, DEBIAN-CVE-2026-112394, ECHO-42fe-1e53-4182, GHSA-4558-3h8r-v8xp, PYSEC-2026-4327, UBUNTU-CVE-2026-112394.