Critical 9.2Published Oct 19, 2026

CVE-2026-112393Pillow: Heap buffer overflow in _tiffWriteProc when saving TIFF to BytesIO

Updated under an hour ago (2026-10-21 05:00 UTC)

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Every CVE for python-pillow Pillow

Exploited in the last 30 days

Pillow is a Python imaging library. From 2.0.0 until 13.0.0, 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(), such as BytesIO. The callback sizes its allocation from the prior buffer size instead of the current write position, allowing an attacker-controlled out-of-line TIFF tag or retained ICC profile to be copied beyond the allocation after libtiff seeks forward. This overflow can crash the process and may allow code execution. Independently, unwritten alignment gaps in compressed TIFF output larger than 64 KiB can disclose stale heap bytes without a crafted tag. File paths and targets with real file descriptors are unaffected. This issue is fixed in version 13.0.0.

CVSS: 9.2 CRITICAL (v4.0, CNA)CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Weakness (CWE): CWE-122
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Undergoing Analysis
Record last updated: Oct 19, 2026
First seen by InfoSec Signals: Oct 19, 2026

Affected products

Affected products

python-pillow Pillow python_pillow:pillow (from the name)	from 2.0.0, < 13.0.0	CNA record

References

https://github.com/python-pillow/Pillow/security/advisories/GHSA-332p-7hrc-92wfx-refsource-confirm
https://github.com/python-pillow/Pillow/commit/11582e5ffbdceb973d5ee593f3105af5a9852b40x-refsource-misc
https://github.com/python-pillow/Pillow/releases/tag/13.0.0x-refsource-misc

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.