Advisory record · GHSA-cp9v-662q-vvx9

Pillow: NULL pointer dereference in Image.merge via an unvalidated band 0

CVSS 8.7 HighEPSS 0.0059 · 48th percentile

Published by the GitHub Advisory Database at 21 Oct 2026, 20:30 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

PackageEcosystemAffectedFixed in
pillowPyPI>=12.0.0, <13.0.013.0.0
Identifiers
GHSA-cp9v-662q-vvx9 · BIT-pillow-2026-112405 · CVE-2026-112405 · PYSEC-2026-4333
Weakness (CWE)
CWE-476
Published
21 Oct 2026
Updated
28 Oct 2026

Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

Pillow versions 12.0.0 up to but not including 13.0.0 are affected by a NULL pointer dereference in Image.merge, which occurs because band 0 is not validated when it is a single-band I or F image. An attacker can trigger it by supplying a crafted file with no recognizable header that is opened and loaded through the IPTC plugin, crashing the worker process in a way the application cannot catch as a Python exception. The fix is to upgrade to Pillow 13.0.0.

Written 31 Oct 2026.

Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

Severity and exploitation

ScoreRatingCVSSVectorSource
8.7 High 4.0 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N CNA (GitHub_M)
  • CISA KEV Not listed.
  • EPSS 0.0059, the 48th percentile, on 7 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

  1. 31 Oct 2026, 14:07 UTC First seen by agentprime
  2. 31 Oct 2026, 14:07 UTC Confirmed by OSV

Sources

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.