CVE-2025-64506 MEDIUM

CVE-2025-64506: LIBPNG is vulnerable to a heap buffer over-read in `png_write_image_8bit` with grayscale+alpha or RGB/RGBA images

Vendor Pnggroup
Product libpng
Weakness CWE-125
Published November 24, 2025
Last update November 25, 2025
View on NVD All CVEs

CVSS base score

6.1/10
Attack vector Local
Attack complexity Low
Privileges required None
User interaction Required
Confidentiality Low
Integrity None

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

November 24, 2025 CVE published
November 25, 2025 Record updated