CVE-2026-112901 · GHSA-xgh8-jp6q-p5x8
Pillow: ReDoS in XbmImagePlugin: 512-byte file stalls Image.open() for minutes
- Risk score
- 50/100
- CVSS
- 6.9 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 is a Python imaging library. Prior to 13.0.0, Pillow's XBM header parser is vulnerable to regular-expression denial of service. In XbmImageFile._open, when an application calls Image.open() on a small crafted XBM file, XbmImagePlugin applies a backtracking expression to the attacker-controlled header before ima…
- Affected
- Pillow (pip) <= 12.3.0
- Fix
- Upgrade Pillow to 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-2026-112901: ReDoS in XbmImagePlugin: 512-byte file stalls Image.open() for minutes (CVSS 6.9 · 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: CWE-1333 (CWE-1333). 43 other warnings in 30 days
Why it is Yellow
- CVSS 6.9 medium
- 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-xgh8-jp6q-p5x8
- https://github.com/python-pillow/Pillow/security/advisories/GHSA-xgh8-jp6q-p5x8
- https://nvd.nist.gov/vuln/detail/CVE-2026-112901
- https://github.com/python-pillow/Pillow/commit/2852a3e3d568997ddec745fc800991f138878f4b
- https://github.com/python-pillow/Pillow/releases/tag/13.0.0
- https://github.com/advisories/GHSA-xgh8-jp6q-p5x8
Original description
Pillow is a Python imaging library. Prior to 13.0.0, Pillow's XBM header parser is vulnerable to regular-expression denial of service. In XbmImageFile._open, when an application calls Image.open() on a small crafted XBM file, XbmImagePlugin applies a backtracking expression to the attacker-controlled header before image dimensions are accepted, stalling a worker for minutes and denying service. This issue is fixed in version 13.0.0.
Last activity 19 Oct 2026. Patch Forecast updates every hour.