CVE-2025-64506

Published Nov 25, 2025

Last updated 9 days ago

Overview

AI description

Automated description summarized from trusted sources.

CVE-2025-64506 is a heap buffer over-read vulnerability found in libpng's `png_write_image_8bit` function. This occurs when processing 8-bit PNG images using the simplified write API with the `convert_to_8bit` option enabled. The vulnerability can be triggered by a specially-formatted 8-bit PNG image. The vulnerability stems from a conditional guard that incorrectly permits 8-bit input to be processed as 16-bit input, leading to reads beyond the allocated buffer. This affects 8-bit grayscale+alpha, RGB/RGBA images, and images with incomplete row data. Exploitation could lead to information disclosure through heap memory leakage or a denial of service due to application crashes.

Description
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.
Source
security-advisories@github.com
NVD status
Analyzed
Products
libpng

Risk scores

CVSS 3.1

Type
Secondary
Base score
6.1
Impact score
4.2
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H
Severity
MEDIUM

Weaknesses

security-advisories@github.com
CWE-125

Social media

Hype score
Not currently trending

Configurations