CVE-2024-28219: Python Pillow Buffer Overflow Vulnerability

CVE-2024-28219 Overview

CVE-2024-28219 is a buffer overflow vulnerability in Python Pillow, a popular Python imaging library. The vulnerability exists in the _imagingcms.c file where the unsafe strcpy function is used instead of the bounds-checked strncpy function. This programming error can lead to memory corruption when processing specially crafted image data, potentially causing application crashes or denial of service conditions.

Critical Impact

Applications using Python Pillow versions before 10.3.0 for image processing are vulnerable to buffer overflow attacks that could result in denial of service through memory corruption when handling malicious image data.

Affected Products

• Python Pillow versions before 10.3.0
• Debian Linux 10.0
• Fedora Linux distributions with vulnerable Pillow packages

Discovery Timeline

• 2024-04-03 - CVE-2024-28219 published to NVD
• 2025-11-04 - Last updated in NVD database

Technical Details for CVE-2024-28219

Vulnerability Analysis

This buffer overflow vulnerability is classified under CWE-680 (Integer Overflow to Buffer Overflow). The flaw resides in the _imagingcms.c source file, which is part of Pillow's color management system integration. The vulnerability occurs because the code uses the strcpy function to copy data into a fixed-size buffer without performing proper bounds checking.

When strcpy is used, it copies characters from a source string to a destination buffer until it encounters a null terminator, with no regard for the destination buffer's actual size. If the source string exceeds the buffer's capacity, memory beyond the buffer boundary gets overwritten, leading to heap or stack corruption depending on where the buffer is allocated.

The attack requires network access but has high complexity to exploit, meaning successful exploitation depends on specific conditions being met. While the vulnerability does not directly impact confidentiality or integrity, it can cause significant availability issues through application crashes.

Root Cause

The root cause is the use of the unsafe strcpy function instead of strncpy or other bounds-checked string copy alternatives in the _imagingcms.c file. This is a classic C programming error where the developer failed to consider buffer size limits when performing string operations. The strcpy function has no built-in mechanism to prevent writing beyond the allocated buffer, making it inherently dangerous when handling input of variable or untrusted length.

Attack Vector

The attack vector is network-based, meaning an attacker can potentially trigger the vulnerability remotely by supplying maliciously crafted image data to an application that uses vulnerable Pillow versions for image processing. The exploitation scenario typically involves:

1. An attacker crafts image data with specially constructed color profile information
2. The victim application processes this image using Pillow's imaging CMS functionality
3. The oversized data is copied using strcpy, causing buffer overflow
4. Memory corruption results in application crash or denial of service

The vulnerability mechanism involves improper string handling in the CMS (Color Management System) component. When Pillow processes images with embedded ICC color profiles, the _imagingcms.c module handles the profile data. If this data contains oversized strings that exceed expected buffer limits, the strcpy call writes beyond the allocated memory region. For detailed technical analysis, see the Pillow Security Release Notes.

Detection Methods for CVE-2024-28219

Indicators of Compromise

• Unexpected crashes in Python applications using Pillow for image processing
• Segmentation fault errors in processes handling image files with color profile data
• Memory corruption patterns in application logs when processing certain image formats
• Abnormal memory usage spikes when handling images with embedded ICC profiles

Detection Strategies

• Audit installed Python packages to identify Pillow versions below 10.3.0 using pip list | grep -i pillow
• Implement static code analysis to detect applications importing vulnerable Pillow versions
• Deploy runtime application monitoring to detect crashes in image processing workflows
• Use software composition analysis (SCA) tools to identify vulnerable dependencies

Monitoring Recommendations

• Monitor application logs for segmentation faults or memory access violations during image processing
• Track crash reports from Python applications that utilize imaging libraries
• Implement alerting for unusual patterns of application restarts in image processing services
• Enable core dump analysis for forensic investigation of potential exploitation attempts

How to Mitigate CVE-2024-28219

Immediate Actions Required

• Upgrade Python Pillow to version 10.3.0 or later immediately
• Audit all applications and services using Pillow as a dependency
• Review Docker containers and virtual environments for outdated Pillow installations
• Update system packages through your distribution's package manager for Debian or Fedora systems

Patch Information

The vulnerability is fixed in Pillow version 10.3.0 and later. The patch replaces the unsafe strcpy function call with strncpy, which accepts a maximum length parameter to prevent buffer overflow conditions. Users should upgrade to the latest stable version of Pillow to receive this and other security fixes.

For detailed patch information, refer to the Pillow Security Release Notes. Distribution-specific patches are available via the Debian LTS Security Announcement and Fedora Package Announcement.

Workarounds

• If immediate upgrade is not possible, limit image processing to trusted sources only
• Implement input validation to reject images with unusually large color profile data
• Consider using containerization to isolate image processing workloads and limit blast radius
• Disable ICC profile processing if not required for your application's functionality

# Upgrade Pillow to patched version
pip install --upgrade "Pillow>=10.3.0"

# Verify installed version
pip show pillow | grep Version

# For Debian-based systems
sudo apt-get update && sudo apt-get upgrade python3-pil

# For Fedora systems
sudo dnf update python3-pillow