Bug 2484837 (CVE-2026-40930)

Summary: CVE-2026-40930 libpng: libpng: Data integrity and availability impact due to improper APNG chunk handling
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: adudiak, ahughes, akhatavk, aos-team-art-private, asdas, dpaolell, fferrari, gotiwari, jdelft, jhorak, jupierce, kaycoth, khosford, kshier, lgarciaa, mbiarnes, mtorre, mvyas, pjindal, ppalepu, ppostler, prdhamdh, rhel-process-autobot, sghai, sidsharm, stcannon, suppawar, teagle, tfitzsim, vlaad, watson-tool-maintainers, yguenane
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in libpng, a library used for processing PNG (Portable Network Graphics) image files. In version 1.8.0, a remote attacker could provide a specially crafted APNG (Animated Portable Network Graphics) file. This flaw allows attacker-controlled data within an ignored chunk to be reinterpreted as a new chunk header, leading to a low impact on data integrity and availability. This could result in unexpected application behavior or a denial of service.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-06-04 16:02:05 UTC
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.