CVE-2026-25646
libpng1.6 - security update
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.
How to fix CVE-2026-25646
To remediate CVE-2026-25646, upgrade the affected package to a fixed version below.
- —upgrade to 1.6.55-r0 or later
- —upgrade to 1.6.37-3+deb11u2 or later
- —upgrade to 1.6.39-2+deb12u3 or later
Is CVE-2026-25646 being exploited?
Low — EPSS is 0.1%, meaning exploitation activity has not been observed at scale.
Affected packages (3)
- from 0, < 1.6.55-r0
- from 0, < 1.6.37-3+deb11u2
- from 0, < 1.6.39-2+deb12u3
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH8.1 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |