Heap-based buffer overflow in Pillow - CVE-2026-112403
Published: November 3, 2026
Vulnerability identifier: #VU158882
CSH Severity: Medium
CVSS v4: 6.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-112403
CWE-ID: CWE-122
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to corrupt heap memory and cause a denial of service.
The vulnerability exists due to a heap-based buffer overflow in Pillow's ImagingJpegDecode() when decoding a lossless SOF3 JPEG after draft() requests scaled output. A remote attacker can supply a specially crafted image to an application that requests scaling through draft() or thumbnail() to cause full-width scanlines to overwrite a heap buffer allocated for scaled-width rows, corrupting memory and potentially crashing the application.
Exploitation requires the linked JPEG library to support lossless decoding.
Affected software
Pillow
Fedora
python-pillow
Fedora
python-pillow
How to mitigate CVE-2026-112403
Install security update from vendor's website.
Pillow - update to 13.0.0
python-pillow - update to 11.3.0-14.fc43
python-pillow - update to 11.3.0-14.fc43