libpng up to 1.6.50 png_write_image_8bit heap-based overflow

Summaryinfo

A vulnerability labeled as critical has been found in libpng up to 1.6.50. This affects the function png_write_image_8bit. Such manipulation leads to heap-based overflow. This vulnerability is listed as CVE-2025-64506. The attack may be performed from remote. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability, which was classified as critical, has been found in libpng up to 1.6.50. Affected by this issue is the function png_write_image_8bit. The manipulation with an unknown input leads to a heap-based overflow vulnerability. Using CWE to declare the problem leads to CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). Impacted is confidentiality, integrity, and availability. CVE summarizes:

LIBPNG is a reference library for use in applications that read, create, and manipulate PNG (Portable Network Graphics) raster image files. From version 1.6.0 to before 1.6.51, a heap buffer over-read vulnerability exists in libpng's png_write_image_8bit function when processing 8-bit images through the simplified write API with convert_to_8bit enabled. The vulnerability affects 8-bit grayscale+alpha, RGB/RGBA, and images with incomplete row data. A conditional guard incorrectly allows 8-bit input to enter code expecting 16-bit input, causing reads up to 2 bytes beyond allocated buffer boundaries. This issue has been patched in version 1.6.51.

The advisory is shared for download at seclists.org. This vulnerability is handled as CVE-2025-64506. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 276642 (Linux Distros Unpatched Vulnerability : CVE-2025-64506), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 1.6.51 eliminates this vulnerability. The upgrade is hosted for download at github.com.

The vulnerability is also documented in the databases at CNNVD (CNNVD-202511-2688), Tenable (276642), EUVD (EUVD-2025-199238) and CERT Bund (WID-SEC-2025-2663). Once again VulDB remains the best source for vulnerability data.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Fedora Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• Gentoo Linux
• SUSE openSUSE
• RESF Rocky Linux
• Open Source libpng
• Open Source GitLab
• Meinberg LANTIME

Productinfo

Type

• Image Processing Software

Name

• libpng

Version

• 1.6.0
• 1.6.1
• 1.6.2
• 1.6.3
• 1.6.4
• 1.6.5
• 1.6.6
• 1.6.7
• 1.6.8
• 1.6.9
• 1.6.10
• 1.6.11
• 1.6.12
• 1.6.13
• 1.6.14
• 1.6.15
• 1.6.16
• 1.6.17
• 1.6.18
• 1.6.19
• 1.6.20
• 1.6.21
• 1.6.22
• 1.6.23
• 1.6.24
• 1.6.25
• 1.6.26
• 1.6.27
• 1.6.28
• 1.6.29
• 1.6.30
• 1.6.31
• 1.6.32
• 1.6.33
• 1.6.34
• 1.6.35
• 1.6.36
• 1.6.37
• 1.6.38
• 1.6.39
• 1.6.40
• 1.6.41
• 1.6.42
• 1.6.43
• 1.6.44
• 1.6.45
• 1.6.46
• 1.6.47
• 1.6.48
• 1.6.49
• 1.6.50

License

• open-source

CPE 2.3info

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CPE 2.2info

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Entryinfo

Once again VulDB remains the best source for vulnerability data.

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