CVE-2026-112393
Pillow: Heap buffer overflow in _tiffWriteProc when saving TIFF to BytesIO
Pillow can write attacker-chosen data past the end of a heap buffer when it saves a TIFF image to an in-memory destination such as io.BytesIO rather than to a file. The same code also copies leftover heap memory from the process into the saved file. Anyone who can supply an image to a service that opens it and re-saves it as TIFF this way can trigger this with default settings.
- python-pillow Pillow
- Critical
- CVSS 9.2
- EPSS 0.53%
- Fixed version listed
What to do
Fixed version listed
Affected products
| Product | Affected | Fixed in |
|---|---|---|
| python-pillow Pillow | >= 2.0.0, < 13.0.0 | None listed |
Affected packages
| Package | Affected | Fixed in | Advisory |
|---|---|---|---|
| Pillow (PyPI) | >= 2.0.0, < 13.0.0 | 13.0.0 | GHSA-332p-7hrc-92wf |
Advisories and fixes
- Public exploit github.com
Scores and signals
- Exploitation
- No known exploitation
- Severity
- Critical, CVSS 9.2 (v4.0, scored by GitHub)
- EPSS
- 0.53% chance of exploitation in the next 30 days (EPSS from FIRST, as of Oct 23, 2026)
- CISA's SSVC decision points
- Exploitation: proof of concept. Automatable: no. Technical impact: total. As of Oct 19, 2026.
- Weakness
- CWE-122: Heap-based Buffer Overflow
- Vendor
- python-pillow, Pillow
Timeline
- GitHub published advisory GHSA-332p-7hrc-92wf (critical). Fixed in 13.0.0.