Medium severity · published Nov 24, 2025
CVE-2025-64506
LIBPNG is vulnerable to a heap buffer over-read in `png_write_image_8bit` with grayscale+alpha or RGB/RGBA images
6.1
CVSS
0.2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 4% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
libpng · pnggroup
>= 1.6.0, < 1.6.51 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-64506
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-64506
Patch
https://github.com/pnggroup/libpng/commit/2bd84c019c300b78e811743fbcddb67c9d9bf821
Issue Tracking
https://github.com/pnggroup/libpng/pull/749
Vendor Advisory
https://github.com/pnggroup/libpng/security/advisories/GHSA-qpr4-xm66-hww6
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