Integer Overflow in Pillow Python Imaging Library Affects Multiple Versions
CVE-2026-96641

6.5MEDIUM

Key Information:

Vendor

Python-pillow

Status
Pillow
Vendor
CVE Published:
21 October 2026

What is CVE-2026-96641?

The Pillow Python imaging library has a vulnerability where prior to version 13.0.0, it fails to handle negative glyph advances properly, which can lead to a signed C integer overflow. This occurs during text-width accumulation in src/_imaging.c when using specific functions like getlength() or getsize(). This improper validation may result in logic integrity errors or resource consumption issues within applications, leading to potential service disruptions. The issue has been resolved in version 13.0.0.

Affected Version(s)

Pillow < 13.0.0

References

https://github.com/python-pillow/Pillow/security/advisori...
x_refsource_CONFIRM
https://github.com/python-pillow/Pillow/pull/10010
x_refsource_MISC
https://github.com/python-pillow/Pillow/commit/80de4be9e3...
x_refsource_MISC

CVSS V3.1

Score:
6.5
Severity:
MEDIUM
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
Required
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.