Overview
CVE-2025-66293 is a high-severity vulnerability affecting libpng, a widely used library for handling PNG image files. This vulnerability, specifically an out-of-bounds read, resides within the simplified API of libpng and can be triggered when processing certain valid PNG images. Successful exploitation could lead to information disclosure or denial-of-service.
Technical Details
The vulnerability stems from an out-of-bounds read in libpng’s simplified API when processing valid palette PNG images with partial transparency and gamma correction. Specifically, the issue occurs when reading beyond the `png_sRGB_base[512]` array, potentially reading up to 1012 bytes beyond the allocated memory. The vulnerability is triggered due to improper internal state management within libpng when handling these specific types of PNG images. While the PNG files themselves are valid according to the PNG specification, the flaw lies within libpng’s processing logic.
CVSS Analysis
- Severity: HIGH
- CVSS Score: 7.1
- This CVSS score reflects the potential for exploitation and the impact it could have on affected systems. The vulnerability allows for out-of-bounds memory access, which could be leveraged for more significant attacks.
Possible Impact
Exploitation of CVE-2025-66293 could have several significant impacts:
- Information Disclosure: An attacker could potentially read sensitive data from memory beyond the intended buffer.
- Denial of Service (DoS): The out-of-bounds read could cause the application using libpng to crash, leading to a denial of service.
Mitigation and Patch Steps
The recommended mitigation for CVE-2025-66293 is to upgrade to libpng version 1.6.52 or later. This version contains the necessary patches to address the out-of-bounds read vulnerability.
- Identify Affected Systems: Determine which systems and applications are using vulnerable versions of libpng.
- Upgrade libpng: Upgrade to libpng version 1.6.52 or later. Follow the specific upgrade instructions for your operating system or software package manager.
- Verify the Patch: After upgrading, verify that the new version is correctly installed and that the vulnerability is no longer present.
