All vulnerabilities
CVE-2026-112892GHSA-gg2r-wvfm-q9rx

Pillow: MSP RLE decoder expands a tiny file into unbounded memory

python-pillow pillowpipLibraries & packages
Open in ThreatlineRecord JSON
CVSS
8.7High
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.29%Chance of exploitation activity in the next 30 days, higher than 20% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in13.0.0Fixed versionGitHub
Published19 Oct 2026Updated 22 Oct 2026CVE List

What fixes it

  • 13.0.0pillow, pipGitHub
  • 13.0.0pillow, PyPIOSVpip install "pillow>=13.0.0"

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

Description

Summary

The MSP RLE decoder expands run-length data into an in-memory buffer with no cap tied to the declared image size. A small file that passes the pixel-count check can force hundreds of megabytes or more of allocation when the application loads pixels.

Details

The MSP decoder writes each run into an unbounded io.BytesIO and can expand roughly 85x per run:

  • src/PIL/MspImagePlugin.py:144-146

Impact

Memory-exhaustion denial of service from a tiny crafted image in any application that loads pixels. The expansion is decoupled from the declared pixel count, so MAX_IMAGE_PIXELS does not bound it.

Text from GitHub Advisory Database

Affected versions 53

  • pillow, pip>= 4.1.0, < 13.0.0GitHub
  • Pillowaffected: >= 4.1.0, < 13.0.0CVE List
  • pillow, PyPIfrom 4.1.0, fixed in 13.0.0OSV
  • pillow, PyPI10.0.0OSV
  • pillow, PyPI10.0.1OSV
  • pillow, PyPI10.1.0OSV
  • pillow, PyPI10.2.0OSV
  • pillow, PyPI10.3.0OSV
  • pillow, PyPI10.4.0OSV
  • pillow, PyPI11.0.0OSV
  • pillow, PyPI11.1.0OSV
  • pillow, PyPI11.2.1OSV
  • pillow, PyPI11.3.0OSV
  • pillow, PyPI12.0.0OSV
  • pillow, PyPI12.1.0OSV
  • pillow, PyPI12.1.1OSV
  • pillow, PyPI12.2.0OSV
  • pillow, PyPI12.3.0OSV
  • pillow, PyPI4.1.0OSV
  • pillow, PyPI4.1.1OSV
  • pillow, PyPI4.2.0OSV
  • pillow, PyPI4.2.1OSV
  • pillow, PyPI4.3.0OSV
  • pillow, PyPI5.0.0OSV
  • pillow, PyPI5.1.0OSV
  • pillow, PyPI5.2.0OSV
  • pillow, PyPI5.3.0OSV
  • pillow, PyPI5.4.0OSV
  • pillow, PyPI5.4.0.dev0OSV
  • pillow, PyPI5.4.1OSV
  • pillow, PyPI6.0.0OSV
  • pillow, PyPI6.1.0OSV
  • pillow, PyPI6.2.0OSV
  • pillow, PyPI6.2.1OSV
  • pillow, PyPI6.2.2OSV
  • pillow, PyPI7.0.0OSV
  • pillow, PyPI7.1.0OSV
  • pillow, PyPI7.1.1OSV
  • pillow, PyPI7.1.2OSV
  • pillow, PyPI7.2.0OSV
  • pillow, PyPI8.0.0OSV
  • pillow, PyPI8.0.1OSV
  • pillow, PyPI8.1.0OSV
  • pillow, PyPI8.1.1OSV
  • pillow, PyPI8.1.2OSV
  • pillow, PyPI8.2.0OSV
  • pillow, PyPI8.3.0OSV
  • pillow, PyPI8.3.1OSV
  • pillow, PyPI8.3.2OSV
  • pillow, PyPI8.4.0OSV
  • pillow, PyPI9.0.0OSV
  • pillow, PyPI9.0.1OSV
  • pillow, PyPI9.1.0OSV

References 5