High severity · published Oct 21, 2026
CVE-2026-96778
Pillow: Heap buffer overflow writing JPEG comment after ICC profile fills buffer
New
8.8
CVSS
0.5%
EPSS
No
On KEV
Description
Pillow is a Python imaging library. From 9.4.0 until 13.0.0, ImagingJpegEncode() in src/libImaging/JpegEncode.c can call jpeg_write_marker() for a JPEG COM comment when an ICC profile has exactly filled the 65536-byte encoder buffer. libjpeg writes one byte before checking the exhausted free_in_buffer counter, which then wraps and permits the attacker-controlled comment and subsequent compressed image data to overwrite adjacent heap memory. Re-saving an untrusted image as JPEG while preserving its ICC profile and forwarded comment can crash the process and may enable code execution in suitable runtime and heap layouts. This issue is fixed in version 13.0.0.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 43% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PI
Pillow · python-pillow
>= 9.4.0, < 13.0.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-96778
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-96778
Patch
https://github.com/python-pillow/Pillow/commit/02561b8dc6117d5670d4b469fecdd02c70854f9b
Issue Tracking
https://github.com/python-pillow/Pillow/pull/10124
Release Notes
https://github.com/python-pillow/Pillow/releases/tag/13.0.0
Vendor Advisory
https://github.com/python-pillow/Pillow/security/advisories/GHSA-g7cr-3p24-7wf7
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