NIXPKGS-2026-1874

GitHub issue published 6 hours ago

LIBPNG: Chunk smuggling in push-mode APNG parser via unconsumed chunk body

Permalink CVE-2026-40930

5.4 MEDIUM

CVSS version (CVSS): 3.1
Attack Vector (AV): Network (N)
Attack Complexity (AC): Low (L)
Privileges Required (PR): None (N)
User Interaction (UI): Required (R)
Scope (S): Unchanged (U)
Confidentiality (C): None (N)
Integrity (I): Low (L)
Availability (A): Low (L)
Modified Attack Vector (MAV): Network (N)
Modified Attack Complexity (MAC): Low (L)
Modified Privileges Required (MPR): None (N)
Modified User Interaction (MUI): Required (R)
Modified Confidentiality (MC): None (N)
Modified Scope (MS): Unchanged (U)
Modified Integrity (MI): Low (L)
Modified Availability (MA): Low (L)

updated 6 hours ago by @LeSuisse Activity log

Created suggestion 11 hours ago
@LeSuisse ignored
3 packages
- libpng12
- perlPackages.ImagePNGLibpng
- perl5Packages.ImagePNGLibpng
6 hours ago
@LeSuisse accepted 6 hours ago
@LeSuisse published on GitHub 6 hours ago

LIBPNG: Chunk smuggling in push-mode APNG parser via unconsumed chunk body

LIBPNG is a reference library for use in applications that process PNG (Portable Network Graphics) raster image files. In version 1.8.0, three inter-frame chunk discard paths in the push-mode APNG parser clear the chunk-header flag without consuming the chunk body and CRC, allowing attacker-controlled bytes inside an ignored ancillary chunk to be reinterpreted as a fresh chunk header on the next call to `png_process_data`. Commit faf06924688b62d7c1654b5ceddedbde66ffadb4 fixes the issue.