CVE-2026-112402 · GHSA-7mwm-ghpf-9vrm
Pillow: Double free in ImagingScaleAffine on calloc failure via Image.transform
- Risk score
- 70/100
- CVSS
- 8.7 v4.0
- Exploit chance (30 days)
- 0.4%
- Published
- 19 Oct 2026
Open in the live forecast Today's forecast
What to know
- What it is
- Pillow has a double free vulnerability in ImagingScaleAffine on calloc failure via Image.transform, which can crash the process and corrupt memory. An attacker can trigger this by driving a large Image.transform() operation under memory pressure.
- Affected
- {'products': ['Pillow'], 'packages': [{'ecosystem': 'pip', 'name': 'Pillow', 'vulnerable': '<= 12.3.0', 'patched': '13.0.0'}]}
- Fix
- Upgrade to version 13.0.0 or later
- Exploitation
- No known exploitation
Story map
At a glance
Pillow: Amber, patch this week. Pillow has a heap buffer overflow and stale-heap disclosure in _tiffWriteProc when saving compressed TIFF data through libtiff to a target without a usable fileno(). This can crash the process and may allow code execution.
The flaws
- CVE-2026-112402: Double free in ImagingScaleAffine on calloc failure via Image.transform (CVSS 8.7 · EPSS 0%)
- CVE-2026-112393: Heap buffer overflow in _tiffWriteProc when saving TIFF to BytesIO (CVSS 9.2 · EPSS 1%)
- CVE-2026-96639: Pillow multi-frame loaders can reuse stale native image storage after mode transitions (CVSS 9.8 · EPSS 1%)
- CVE-2026-112900: Argument Injection in Ghostscript call, potentially leading into RCE (CVSS 9.2 · EPSS 0%)
The fix
Upgrade Pillow: 13.0.0 or later on your release line
Who is exposed: {'products': ['Pillow'], 'packages': ['Pillow'], 'versions': ['>= 2.0.0, < 13.0.0']}
Where it stands
- Public proof of concept
- 1 outlet covering it
How it unfolded
- 23 Oct, The Hacker News (press): Critical Flaw in Python’s Popular Pillow Image Library Allows Code Execution via a Crafted Image
Connects to
- Same weakness: Use-after-free (CWE-416). 399 other warnings in 30 days
Why it is Amber
- CVSS 8.7 high
- Remotely exploitable without logging in
- On your watchlist: PyPI
Affected packages
| Package | Ecosystem | Vulnerable | Fixed in |
|---|---|---|---|
| Pillow | pip | <= 12.3.0 | 13.0.0 |
References
- https://github.com/advisories/GHSA-7mwm-ghpf-9vrm
- https://github.com/python-pillow/Pillow/security/advisories/GHSA-7mwm-ghpf-9vrm
- https://nvd.nist.gov/vuln/detail/CVE-2026-112402
- https://github.com/python-pillow/Pillow/commit/aafa6c75f7cdabb9f409a8aac7c780bea31d08d9
- https://github.com/python-pillow/Pillow/releases/tag/13.0.0
- https://github.com/advisories/GHSA-7mwm-ghpf-9vrm
Original description
Pillow is a Python imaging library. Prior to 13.0.0, Pillow can double free image memory when ImagingScaleAffine encounters a selective allocation failure. The affected fast path handles Transform.EXTENT or pure scale-and-translate Transform.AFFINE operations with the default NEAREST resampling. The output image allocation must succeed while the additional per-column lookup allocation fails, after which the error path deletes image storage that later cleanup releases again. An attacker who can drive such a large Image.transform() operation under memory pressure may trigger the failure. This can crash the process and may corrupt memory. This issue is fixed in version 13.0.0.
Last activity 19 Oct 2026. Patch Forecast updates every hour.