CVE-2026-40930 (GCVE-0-2026-40930)

Vulnerability from cvelistv5 – Published: 2026-06-04 14:34 – Updated: 2026-06-04 16:37
VLAI
Title
LIBPNG: Chunk smuggling in push-mode APNG parser via unconsumed chunk body
Summary
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.
Severity
5.4 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-04 16:37 UTC
CWE
  • CWE-436 - Interpretation Conflict
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7763 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
pnggroup libpng Affected: = 1.8.0
guessed Create a notification for this product.
pnggroup libpng-apng Affected: >= 1.6.49, <= 1.6.57
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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