CVE-2025-64505

LIBPNG is vulnerable to a heap buffer overflow in `png_do_quantize` via malformed palette index

Published Nov 24, 2025 CVSS 3.1 · 6.1 Medium EPSS < 1% KEV · Not listed
Description
LIBPNG is a reference library for use in applications that read, create, and manipulate PNG (Portable Network Graphics) raster image files. Prior to version 1.6.51, a heap buffer over-read vulnerability exists in libpng's png_do_quantize function when processing PNG files with malformed palette indices. The vulnerability occurs when palette_lookup array bounds are not validated against externally-supplied image data, allowing an attacker to craft a PNG file with out-of-range palette indices that trigger out-of-bounds memory access. This issue has been patched in version 1.6.51.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Debian DLA Debian DLA DLA-4396-1 libpng1.6 security update
Debian DSA Debian DSA DSA-6076-1 libpng1.6 security update
Ubuntu USN Ubuntu USN USN-7924-1 libpng vulnerabilities
Ubuntu USN Ubuntu USN USN-8081-1 libpng vulnerabilities
History
Type Values Removed Values Added
CPEs cpe:2.3:a:libpng:libpng:*:*:*:*:*:*:*:*
Type Values Removed Values Added
First Time appeared Libpng
Libpng libpng
Vendors & Products Libpng
Libpng libpng
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description LIBPNG is a reference library for use in applications that read, create, and manipulate PNG (Portable Network Graphics) raster image files. Prior to version 1.6.51, a heap buffer over-read vulnerability exists in libpng's png_do_quantize function when processing PNG files with malformed palette indices. The vulnerability occurs when palette_lookup array bounds are not validated against externally-supplied image data, allowing an attacker to craft a PNG file with out-of-range palette indices that trigger out-of-bounds memory access. This issue has been patched in version 1.6.51.
Title LIBPNG is vulnerable to a heap buffer overflow in `png_do_quantize` via malformed palette index
Weaknesses CWE-125
References
Metrics cvssV3_1

{'score': 6.1, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Nov 25, 2025, 6:55 PM
Reserved
Nov 5, 2025, 7:12 PM
Status
Analyzed
Published
Nov 25, 2025, 12:15 AM
Modified
Oct 18, 2026, 8:10 PM
Severity
Moderate
Public date
Nov 24, 2025, 11:38 PM