CVE-2026-112896 · GHSA-pchr-8j38-3x4p
Pillow: TIFF encoder ColorMap plane-size mismatch causes a heap out-of-bounds read
- Risk score
- 67/100
- CVSS
- 8.8 v4.0
- Exploit chance (30 days)
- 0.3%
- Published
- 19 Oct 2026
Open in the live forecast Today's forecast
What to know
- What it is
- Pillow's TIFF encoder has a heap out-of-bounds read vulnerability when reading a ColorMap buffer with inconsistent BitsPerSample. An attacker can disclose heap memory or crash the process by re-encoding a crafted TIFF.
- Affected
- {'products': ['Pillow'], 'packages': ['Pillow'], 'versions': ['<= 12.3.0']}
- 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-2026-112896: TIFF encoder ColorMap plane-size mismatch causes a heap out-of-bounds read (CVSS 8.8 · 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: Out-of-bounds read (CWE-125). 347 other warnings in 30 days
Why it is Amber
- CVSS 8.8 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-pchr-8j38-3x4p
- https://github.com/python-pillow/Pillow/security/advisories/GHSA-pchr-8j38-3x4p
- https://nvd.nist.gov/vuln/detail/CVE-2026-112896
- https://github.com/python-pillow/Pillow/commit/d03dc3c587a9b0bdc9e4304d70d59a635a87b742
- https://github.com/python-pillow/Pillow/releases/tag/13.0.0
- https://github.com/advisories/GHSA-pchr-8j38-3x4p
Original description
Pillow is a Python imaging library. Prior to 13.0.0, Pillow's TIFF encoder can read beyond a ColorMap buffer when retained TIFF metadata has a plane size inconsistent with BitsPerSample. A small TIFF can be opened normally and then retain a crafted ColorMap that is reused when the image is saved. An application that re-encodes the attacker's TIFF with libtiff can trigger the out-of-bounds read. This can disclose heap memory in the output or crash the process. This issue is fixed in version 13.0.0.
Last activity 19 Oct 2026. Patch Forecast updates every hour.