High severity · published Jul 14, 2026
CVE-2026-59203
Pillow EpsImagePlugin negative %%BeginBinary byte count causes infinite loop denial of service
7.5
CVSS
0.4%
EPSS
No
On KEV
Description
Pillow is a Python imaging library. From 12.0.0 through 12.2.0, Pillow's EPS parser in PIL/EpsImagePlugin.py accepts a negative byte count in the %%BeginBinary directive, allowing a crafted EPS file to cause Image.open() to seek backwards to the same directive and parse it repeatedly in an infinite loop. 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 34% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PI
Pillow · python-pillow
>= 12.0.0, < 12.3.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-59203
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-59203
Patch
https://github.com/python-pillow/Pillow/commit/03992618118b4a76b6163cd72ab5ecd684133b83
Issue Tracking
https://github.com/python-pillow/Pillow/pull/9708
Release Notes
https://github.com/python-pillow/Pillow/releases/tag/12.3.0
Exploit
https://github.com/python-pillow/Pillow/security/advisories/GHSA-pg7v-jwj7-p798
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