Out-of-bounds Read in Libpng
CVE-2025-64720
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, an out-of-bounds read vulnerability exists in png_image_read_composite when processing palette images with PNG_FLAG_OPTIMIZE_ALPHA enabled. The palette compositing code in png_init_read_transformations incorrectly applies background compositing during premultiplication, violating the invariant component ≤ alpha × 257 required by the simplified PNG API. This issue has been patched in version 1.6.51.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H.
EPSS exploit prediction
EPSS: 0.004 (33.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 33rd percentile — 33.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
- Libpng
- Pnggroup Libpng — versions >= 1.6.0, < 1.6.51
Weakness classification (CWE)
Public proof-of-concept exploits
References
- github.com/pnggroup/libpng/security/advisories/GHSA-hfc7-ph9c-wcww (Exploit, Vendor Advisory)
- github.com/pnggroup/libpng/issues/686 (Exploit, Issue Tracking)
- github.com/pnggroup/libpng/pull/751 (Patch, Issue Tracking)
- github.com/pnggroup/libpng/commit/08da33b4c88cfcd36e5a706558a8d7e0e4773643 (Patch)
Frequently asked questions
- What is CVE-2025-64720?
- CVE-2025-64720 is a high-severity vulnerability in Libpng, classified under Out-of-bounds Read. CVSS score: 7.1/10. Published 2025-11-25.
- How severe is CVE-2025-64720?
- High severity. CVSS v3 base score is 7.1 out of 10.
- Is CVE-2025-64720 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.