CVE-2025-64720

LIBPNG is vulnerable to a buffer overflow in `png_image_read_composite` via incorrect palette premultiplication

HIGH
7.1
CVSS Score
Published: November 24, 2025 at 11:45 PM UTC
Updated: October 18, 2026 at 08:10 PM UTC
2 products affected across 2 vendorsLibpngLibpng

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Severity
HIGH7.1
Exploit prediction
EPSS 0.4%
SSVC
PoC

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, 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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

1.6.0 ≤ v < 1.6.51
Affected range stops below 1.6.51, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (4)

x_refsource_CONFIRMExploitVendor Advisory
Source: cverecord
https://github.com/pnggroup/libpng/security/advisories/GHSA-hfc7-ph9c-wcww
x_refsource_MISCExploitIssue Tracking
Source: cverecord
https://github.com/pnggroup/libpng/issues/686
x_refsource_MISCIssue TrackingPatch
Source: cverecord
https://github.com/pnggroup/libpng/pull/751

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.1HIGHGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
LOW
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-125

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