Vulnerability · Published Oct 19, 2026 · Assigned by GitHub_M
CVE-2026-112402Pillow: Double free in ImagingScaleAffine on calloc failure via Image.transform
High 8.7
In plain English
A high-severity use-after-free in Pillow from python-pillow. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 49% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Pillow is a Python imaging library. Prior to 13.0.0, Pillow can double free image memory when ImagingScaleAffine encounters a selective allocation failure. The affected fast path handles Transform.EXTENT or pure scale-and-translate Transform.AFFINE operations with the default NEAREST resampling. The output image allocation must succeed while the additional per-column lookup allocation fails, after which the error path deletes image storage that later cleanup releases again. An attacker who can drive such a large Image.transform() operation under memory pressure may trigger the failure. This can crash the process and may corrupt memory. This issue is fixed in version 13.0.0.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux:8 | python3-pillow | 5.1.1-33.el8_10 | ALSA-2026:92639 |
| AlmaLinux:8 | python3-pillow-devel | 5.1.1-33.el8_10 | ALSA-2026:92639 |
| AlmaLinux:8 | python3-pillow-doc | 5.1.1-33.el8_10 | ALSA-2026:92639 |
| AlmaLinux:8 | python3-pillow-tk | 5.1.1-33.el8_10 | ALSA-2026:92639 |
| Debian:12 | pillow | no fix listed | DEBIAN-CVE-2026-112402 |
| Debian:13 | pillow | no fix listed | DEBIAN-CVE-2026-112402 |
| Debian:14 | pillow | no fix listed | DEBIAN-CVE-2026-112402 |
| PyPI | pillow | 13.0.0 | GHSA-7mwm-ghpf-9vrm |
| PyPI | pillow | 13.0.0 | PYSEC-2026-4331 |
| Rocky Linux:8 | python-pillow | 0:5.1.1-33.el8_10 | RLSA-2026:92639 |
| Ubuntu:22.04:LTS | pillow | no fix listed | UBUNTU-CVE-2026-112402 |
| Ubuntu:24.04:LTS | pillow | no fix listed | UBUNTU-CVE-2026-112402 |
| Ubuntu:26.04:LTS | pillow | no fix listed | UBUNTU-CVE-2026-112402 |
| Ubuntu:26.10 | pillow | no fix listed | UBUNTU-CVE-2026-112402 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| python-pillow | Pillow | < 13.0.0 |
Weakness: CWE-416 · Vector: 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