CVE-2026-96778: pillow Memory Corruption — Fix

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.

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CVSS v3.1 Score

8.8

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

EPSS — Exploit Prediction

0.0045

Probability of exploitation

0.40%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-787 Out-of-bounds Write

Affected Products

Vendor	Product	Versions
python	pillow	9.4.0 — 13.0.0

References

Advisories & Patches

https://github.com/python-pillow/Pillow/commit/02561b8dc6117d5670d4b469fecdd02c70854f9b https://github.com/python-pillow/Pillow/security/advisories/GHSA-g7cr-3p24-7wf7 https://github.com/python-pillow/Pillow/security/advisories/GHSA-g7cr-3p24-7wf7

Other References

https://github.com/python-pillow/Pillow/pull/10124 https://github.com/python-pillow/Pillow/releases/tag/13.0.0

Frequently Asked Questions

What is CVE-2026-96778? +

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. It has a CVSS v3.1 base score of 8.8 (HIGH).

How severe is CVE-2026-96778? +

CVE-2026-96778 has a CVSS v3.1 score of 8.8 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0045, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-96778? +

CVE-2026-96778 affects products from python, specifically: pillow. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-96778? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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