CVE-2026-59200
Medium
Elevated severity or exploit probability.
CVSS base
7.5
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS — probability of exploitation (30 days)
0.4%
32.5th percentile
CISA KEV
Not listed
Weakness / dates
CWE-400
Published 2026-07-14 · modified 2026-07-21
CVSS breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
| Attack Vector | N | Network |
| Attack Complexity | L | Low |
| Privileges Required | N | None |
| User Interaction | N | None |
| Scope | U | Unchanged |
| Confidentiality | N | None |
| Integrity | N | None |
| Availability | H | High |
Timeline
- 2026-07-14 — Published (NVD)
- 2026-07-21 — Last modified (NVD)
Description
Pillow is a Python imaging library. From 5.1.0 until 12.3.0, PdfParser.PdfStream.decode() in PIL/PdfParser.py calls zlib.decompress() with bufsize set to the PDF stream Length field without bounding the decompressed output size, allowing a crafted FlateDecode PDF stream to exhaust memory from a small file. This issue is fixed in version 12.3.0.
Affected
References
- https://github.com/python-pillow/Pillow/commit/f7a31ea75e460e108c37126da1f47812f21f6b09
- https://github.com/python-pillow/Pillow/pull/9718
- https://github.com/python-pillow/Pillow/releases/tag/12.3.0
- exploit https://github.com/python-pillow/Pillow/security/advisories/GHSA-jjj6-mw9f-p565
- exploit https://github.com/python-pillow/Pillow/security/advisories/GHSA-jjj6-mw9f-p565