CVE-2025-64505 | LIBPNG is vulnerable to a heap buffer overflow in `png_do_quantize` via malformed palette index

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.

Published: 2025-11-25 Last update: 2025-11-26 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2025-64505 is rated Low Risk (24.8/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.01%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-64505

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-11-25 0.01%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-64505

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.1 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.8 4.2 [email protected]

Weakness enumeration for CVE-2025-64505

OS Trackers for CVE-2025-64505

vendor priority summary link
alpine medium CVE-2025-64505: 1 source package rows (libpng); 19 state rows across 5 repos (3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 4, open 15. https://security.alpinelinux.org/vuln/CVE-2025-64505
debian not yet assigned CVE-2025-64505 not yet assigned priority: Debian including 1 source packages (libpng1.6), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2025-64505
gentoo high CVE-2025-64505: 1 GLSA(s) (202511-06), 1 atom(s) (media-libs/libpng); latest impact high. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2025-64505
redhat medium https://access.redhat.com/security/cve/CVE-2025-64505
suse medium CVE-2025-64505 severity moderate: SUSE including 295 source package names (2.0.4-5.8.229:libpng16-16-1.6.34-150000.3.12.1, 2.1.3-7.76:libpng16-16-1.6.43-slfo.1.1_2.1, …), 868 product×package rows across 310 product lines (Container private-registry/harbor-portal, Container suse/manager/5.0/x86_64/server, … (310 product lines)): Fixed 569, Known Affected 231, Known Not Affected 61, First Fixed 7. https://www.suse.com/security/cve/CVE-2025-64505/
ubuntu medium CVE-2025-64505 medium priority: Ubuntu including 5 source packages (chromium-browser, firefox, libpng, libpng1.6, thunderbird), 30 status rows across 9 suites (bionic, focal, jammy, noble, plucky, questing, trusty, upstream, xenial): not-affected 11, released 10, DNE 4, needs-triage 4, ignored 1. https://ubuntu.com/security/CVE-2025-64505

Affected software / configurations for CVE-2025-64505

Vendor Product Version Raw CPE
libpng libpng < 1.6.51 cpe:2.3:a:libpng:libpng:*:*:*:*:*:*:*:*

References for CVE-2025-64505

cvelogic Threat Intelligence