{"id":"CVE-2026-40930","state":"PUBLISHED","title":"LIBPNG: Chunk smuggling in push-mode APNG parser via unconsumed chunk body","description":"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.","publishedAt":"2026-06-04T14:34:51.843Z","updatedAt":"2026-06-04T16:37:38.286Z","severity":{"score":5.4,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L","source":"GitHub_M"},"assigner":"GitHub_M","products":["pnggroup libpng","pnggroup libpng-apng"],"affected":[{"vendor":"pnggroup","product":"libpng","versions":[{"version":"= 1.8.0","status":"affected"}]},{"vendor":"pnggroup","product":"libpng-apng","versions":[{"version":">= 1.6.49, <= 1.6.57","status":"affected"}]}],"references":["https://github.com/pnggroup/libpng/security/advisories/GHSA-c4v6-gxrq-6g2x","https://github.com/pnggroup/libpng/commit/faf06924688b62d7c1654b5ceddedbde66ffadb4","http://www.openwall.com/lists/oss-security/2026/05/15/21"],"weaknesses":["CWE-436"],"ingestedAt":"2026-10-29T20:11:57.932Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/40xxx/CVE-2026-40930.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-40930","state":"PUBLISHED","datePublished":"2026-06-04T14:34:51.843Z","dateUpdated":"2026-06-04T16:37:38.286Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-04-15T20:40:15.518Z"},"containers":{"cna":{"title":"LIBPNG: Chunk smuggling in push-mode APNG parser via unconsumed chunk body","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"pnggroup","product":"libpng","versions":[{"version":"= 1.8.0","status":"affected"}]},{"vendor":"pnggroup","product":"libpng-apng","versions":[{"version":">= 1.6.49, <= 1.6.57","status":"affected"}]}],"references":[{"url":"https://github.com/pnggroup/libpng/security/advisories/GHSA-c4v6-gxrq-6g2x","name":"https://github.com/pnggroup/libpng/security/advisories/GHSA-c4v6-gxrq-6g2x","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/pnggroup/libpng/commit/faf06924688b62d7c1654b5ceddedbde66ffadb4","name":"https://github.com/pnggroup/libpng/commit/faf06924688b62d7c1654b5ceddedbde66ffadb4","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"LOW","baseScore":5.4,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"LOW","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-436","lang":"en","description":"CWE-436: Interpretation Conflict","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-06-04T14:34:51.843Z"},"source":{"advisory":"GHSA-c4v6-gxrq-6g2x","discovery":"UNKNOWN"}},"adp":[{"title":"CVE Program Container","references":[{"url":"http://www.openwall.com/lists/oss-security/2026/05/15/21"}],"providerMetadata":{"shortName":"CVE","orgId":"af854a3a-2127-422b-91ae-364da2661108","dateUpdated":"2026-06-04T15:05:19.991Z"}},{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-06-04T16:37:21.465127Z","id":"CVE-2026-40930","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-06-04T16:37:38.286Z"}}]}}}