High severity · published Jul 14, 2026
CVE-2026-59200
Pillow: Decompression Bomb DoS via PdfParser.PdfStream.decode()
7.5
CVSS
0.4%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 32% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PI
Pillow · python-pillow
>= 5.1.0, < 12.3.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-59200
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-59200
Patch
https://github.com/python-pillow/Pillow/commit/f7a31ea75e460e108c37126da1f47812f21f6b09
Issue Tracking
https://github.com/python-pillow/Pillow/pull/9718
Release Notes
https://github.com/python-pillow/Pillow/releases/tag/12.3.0
Exploit
https://github.com/python-pillow/Pillow/security/advisories/GHSA-jjj6-mw9f-p565
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