CVE-2026-55380: CWE-789: Memory Allocation with Excessive Size Value in python-pillow Pillow
Pillow is a Python imaging library. Prior to 12.3.0, PIL/GdImageFile.py GdImageFile._open() read image dimensions from the GD 2.x header and stored them in self._size without calling Image._decompression_bomb_check(), allowing a crafted .gd file to trigger excessive C-heap allocation when loaded. This issue is fixed in version 12.3.0.
AI Analysis
Technical Summary
CVE-2026-55380 is a high-severity vulnerability in the Pillow Python imaging library affecting versions prior to 12.3.0. The vulnerability arises in the PIL/GdImageFile.py module where the _open() function reads image dimensions from a GD 2.x header and assigns them to self._size without calling Image._decompression_bomb_check(). This omission allows a crafted .gd file to trigger excessive memory allocation on the C heap when loaded, potentially causing denial of service due to resource exhaustion. The issue is resolved in version 12.3.0 of Pillow.
Potential Impact
An attacker can supply a specially crafted .gd image file that causes the Pillow library to allocate excessive memory, leading to denial of service conditions by exhausting system resources. There is no indication of confidentiality or integrity impact, only availability is affected.
Mitigation Recommendations
Upgrade Pillow to version 12.3.0 or later, where this vulnerability is fixed. Patch status is confirmed by the version fix information. No other mitigation is indicated.
CVE-2026-55380: CWE-789: Memory Allocation with Excessive Size Value in python-pillow Pillow
Description
Pillow is a Python imaging library. Prior to 12.3.0, PIL/GdImageFile.py GdImageFile._open() read image dimensions from the GD 2.x header and stored them in self._size without calling Image._decompression_bomb_check(), allowing a crafted .gd file to trigger excessive C-heap allocation when loaded. This issue is fixed in 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-2026-55380 is a high-severity vulnerability in the Pillow Python imaging library affecting versions prior to 12.3.0. The vulnerability arises in the PIL/GdImageFile.py module where the _open() function reads image dimensions from a GD 2.x header and assigns them to self._size without calling Image._decompression_bomb_check(). This omission allows a crafted .gd file to trigger excessive memory allocation on the C heap when loaded, potentially causing denial of service due to resource exhaustion. The issue is resolved in version 12.3.0 of Pillow.
Potential Impact
An attacker can supply a specially crafted .gd image file that causes the Pillow library to allocate excessive memory, leading to denial of service conditions by exhausting system resources. There is no indication of confidentiality or integrity impact, only availability is affected.
Mitigation Recommendations
Upgrade Pillow to version 12.3.0 or later, where this vulnerability is fixed. Patch status is confirmed by the version fix information. No other mitigation is indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-06-16T18:57:40.182Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a4bfce927e9c7971910b4c5
Added to database: 07/06/2026, 19:07:21 UTC
Last enriched: 07/06/2026, 19:21:26 UTC
Last updated: 07/06/2026, 19:52:08 UTC
Views: 5
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