CVE-2026-96639
Reported by GitHub_M · Published October 21, 2026
Pillow is a Python imaging library. From 11.0.0 until 13.0.0, multi-frame loaders can retain an ImagingCore allocation created for a narrow frame mode while a later frame of the same dimensions changes the logical mode and decoder tiles to wider RGB or CMYK data. ImageFile.load_prepare() reuses the stale native storage because _im is non-null without verifying that its mode and size still match. Crafted PSD, MPO, DCX, or MIC frame transitions can then write wider pixels into the narrow allocation, causing native out-of-bounds writes and crashes. The MPO path can also cause a native over-read and, in demonstrated runtime-specific profiles, command execution. This issue is fixed in version 13.0.0.
Risk Scores
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| python-pillow | Pillow | >= 11.0.0, < 13.0.0 |
| chainguard | nemo-gym | 0 |
| chainguard | nemo-rl-cuda-13.0 | 0 |
| chainguard | superset-fips-6.1 | 0 |
| python-pillow | Pillow | 11.0.0 |
| chainguard | py3-pytorch-cuda-13.0 | 0 |
| PyPI | Pillow | 11.0.0 |
Timeline
- Oct 21, 2026 CVE Published
- Oct 22, 2026 EPSS Score
- Oct 22, 2026 Coalition ESS Score
- Oct 25, 2026 EPSS Score
- Oct 29, 2026 EPSS Score
- Oct 29, 2026 CVE Updated
- Oct 30, 2026 Security Advisory
- Oct 31, 2026 EPSS Score
References
- https://github.com/python-pillow/Pillow/security/advisories/GHSA-v9pv-5gc8-w2m6 x_refsource_CONFIRM
- https://github.com/python-pillow/Pillow/pull/10105 x_refsource_MISC
- https://github.com/python-pillow/Pillow/commit/78d97d994579aef81aafe123773d525f40f2522a x_refsource_MISC
- https://github.com/python-pillow/Pillow/releases/tag/13.0.0 x_refsource_MISC
- https://nvd.nist.gov/vuln/detail/CVE-2026-96639 advisory
- https://github.com/advisories/GHSA-v9pv-5gc8-w2m6 advisory