CVE-2026-25646

HIGH

libpng < 1.6.55 - Buffer Over-read in png_set_quantize()

Title source: llm
STIX 2.1

Description

LIBPNG is a reference library for use in applications that read, create, and manipulate PNG (Portable Network Graphics) raster image files. Prior to 1.6.55, an out-of-bounds read vulnerability exists in the png_set_quantize() API function. When the function is called with no histogram and the number of colors in the palette is more than twice the maximum supported by the user's display, certain palettes will cause the function to enter into an infinite loop that reads past the end of an internal heap-allocated buffer. The images that trigger this vulnerability are valid per the PNG specification. This vulnerability is fixed in 1.6.55.

References (57)

Core 57
Core References

Scores

CVSS v3 8.1
EPSS 0.0095
EPSS Percentile 57.9%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation poc
Automatable no
Technical Impact partial

Details

CWE
CWE-122 CWE-125 CWE-126
Status published
Products (2)
libpng/libpng < 1.6.55
pnggroup/libpng < 1.6.55
Published Feb 10, 2026
Tracked Since Feb 18, 2026