# CVE-2026-112405: Pillow null pointer dereference in Image.merge()

Source: https://junglewise.ai/threats/cve-2026-112405-pillow-is-a-python-imaging-library-from-12-0-0-until-13-0-0  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-19. Updated: 2026-10-19  
License: CC BY 4.0 with a link back

CVE-2026-112405 · Severity: high · CVSS 4 · Published 2026-10-19

Pillow is a Python image processing library used to open and manipulate image files. When processing certain crafted IPTC image files, Pillow's Image.merge() function can crash the Python process due to a null pointer dereference. Applications that automatically open untrusted image files are vulnerable to denial of service.

Technologies: [pillow (PyPI)](https://junglewise.ai/threats/technologies/pillow), [Python Pillow Pillow](https://junglewise.ai/threats/technologies/python-pillow-pillow). Vendors: [PyPI](https://junglewise.ai/threats/vendors/pypi), [Python Pillow](https://junglewise.ai/threats/vendors/python-pillow).

## Quick answers

**Is CVE-2026-112405 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-112405 being exploited in the wild.

**How severe is CVE-2026-112405?** High severity, with a CVSS score of 4, published 19 October 2026.

**Which products and versions are affected?** pillow (PyPI) >= 12.0.0, < 13.0.0, ECOSYSTEM:introduced=12.0.0,fixed=13.0.0; Python Pillow Pillow 12.0.0 to 12.x.

**Is there a fix for CVE-2026-112405?** Yes. pillow (PyPI): upgrade to 13.0.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-112405 attacked?** It is attacked with local access or over the network, in a software library.

**Am I affected by CVE-2026-112405?** Check whether you run pillow (PyPI) or Python Pillow Pillow at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- pillow (PyPI): upgrade to 13.0.0 or later

  ```sh
  pip install "pillow>=13.0.0"
  ```


## Technical details

A validation bypass in Image.merge() skips checking the first input band, allowing 32-bit images backed by image32 storage to be merged as narrower multiband images, leading to null pointer dereference. The vulnerability affects versions 12.0.0 through 12.x; affected code can be reached either by parsing a crafted IPTC file or direct API calls to Image.merge(). This is a local denial-of-service issue fixed by raising ValueError on invalid merge operations in version 13.0.0.

## Affected products

- python-pillow Pillow 12.0.0 to 12.x

## Identifiers

- CVE-2026-112405
- BIT-PILLOW-2026-112405
- GHSA-cp9v-662q-vvx9
- PYSEC-2026-4333

## Timeline

- 2026-10-19: disclosed

## References

- [https://github.com/python-pillow/Pillow/commit/b6ee66e8b2c2c0932bdf65f963268d9f2927ef86](https://github.com/python-pillow/Pillow/commit/b6ee66e8b2c2c0932bdf65f963268d9f2927ef86)
- [https://github.com/python-pillow/Pillow/releases/tag/13.0.0](https://github.com/python-pillow/Pillow/releases/tag/13.0.0)

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