CVE-2026-59205: CWE-787: Out-of-bounds Write in python-pillow Pillow
A high-severity vulnerability (CVE-2026-59205) exists in the Python Pillow imaging library prior to version 12.3.0. The issue involves an out-of-bounds write in the ImageCms.ImageCmsTransform.apply(im, imOut) API, which can cause controlled native heap corruption if the output image mode does not match the transform's declared output mode. This vulnerability has a CVSS score of 7.5 and is fixed in Pillow version 12.3.0.
AI Analysis
Technical Summary
CVE-2026-59205 is an out-of-bounds write vulnerability in the Pillow Python imaging library. Specifically, the ImageCms.ImageCmsTransform.apply(im, imOut) function can trigger controlled native heap corruption when the output image's mode parameter does not match the expected output mode of the transform. This mismatch leads to memory corruption. The vulnerability affects all Pillow versions prior to 12.3.0 and has been addressed in version 12.3.0.
Potential Impact
Exploitation of this vulnerability can lead to controlled native heap corruption, which may cause application crashes or potentially enable further exploitation depending on the context in which Pillow is used. The CVSS score of 7.5 indicates a high severity with network attack vector, low attack complexity, no privileges required, no user interaction, and impact limited to availability (denial of service). There is no indication of confidentiality or integrity impact.
Mitigation Recommendations
This vulnerability is fixed in Pillow version 12.3.0. Users and organizations should upgrade to version 12.3.0 or later to remediate this issue. No other official remediation or temporary fixes are indicated. Patch status is confirmed by the vendor advisory stating the fix is included in version 12.3.0.
CVE-2026-59205: CWE-787: Out-of-bounds Write in python-pillow Pillow
Description
A high-severity vulnerability (CVE-2026-59205) exists in the Python Pillow imaging library prior to version 12.3.0. The issue involves an out-of-bounds write in the ImageCms.ImageCmsTransform.apply(im, imOut) API, which can cause controlled native heap corruption if the output image mode does not match the transform's declared output mode. This vulnerability has a CVSS score of 7.5 and is fixed in Pillow version 12.3.0.
CVSS v3.1
Score 7.5high
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-59205 is an out-of-bounds write vulnerability in the Pillow Python imaging library. Specifically, the ImageCms.ImageCmsTransform.apply(im, imOut) function can trigger controlled native heap corruption when the output image's mode parameter does not match the expected output mode of the transform. This mismatch leads to memory corruption. The vulnerability affects all Pillow versions prior to 12.3.0 and has been addressed in version 12.3.0.
Potential Impact
Exploitation of this vulnerability can lead to controlled native heap corruption, which may cause application crashes or potentially enable further exploitation depending on the context in which Pillow is used. The CVSS score of 7.5 indicates a high severity with network attack vector, low attack complexity, no privileges required, no user interaction, and impact limited to availability (denial of service). There is no indication of confidentiality or integrity impact.
Mitigation Recommendations
This vulnerability is fixed in Pillow version 12.3.0. Users and organizations should upgrade to version 12.3.0 or later to remediate this issue. No other official remediation or temporary fixes are indicated. Patch status is confirmed by the vendor advisory stating the fix is included in version 12.3.0.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-07-02T21:05:02.924Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a56616e68715ace43d27033
Added to database: 07/14/2026, 16:18:54 UTC
Last enriched: 07/21/2026, 19:39:59 UTC
Last updated: 08/26/2026, 22:52:11 UTC
Views: 56
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