{"id":"CVE-2026-112399","state":"PUBLISHED","title":"Pillow: APNG background disposal allocates full canvas before decompression bomb check","description":"Pillow is a Python imaging library. From 8.1.0 until 13.0.0, Pillow can allocate an APNG disposal background at the full canvas size before applying the decompression-bomb check. A crafted APNG with a small first frame, a very large declared canvas, and background disposal or first-frame OP_PREVIOUS reaches PngImageFile._seek while Image.open() positions frame zero. The full-canvas allocation occurs inside Image.open() without requiring pixel loading or frame iteration. This can exhaust memory and deny service. This issue is fixed in version 13.0.0.","publishedAt":"2026-10-19T21:10:11.266Z","updatedAt":"2026-10-28T15:21:14.748Z","severity":{"score":8.7,"label":"High","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["python-pillow Pillow"],"affected":[{"vendor":"python-pillow","product":"Pillow","versions":[{"version":">= 8.1.0, < 13.0.0","status":"affected"}]}],"references":["https://github.com/python-pillow/Pillow/security/advisories/GHSA-5xm2-6676-qcp9","https://github.com/python-pillow/Pillow/commit/f1acfc54c53502948d0d14121872061df931db48","https://github.com/python-pillow/Pillow/releases/tag/13.0.0"],"weaknesses":["CWE-789"],"ingestedAt":"2026-10-29T20:10:43.281Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/112xxx/CVE-2026-112399.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-112399","state":"PUBLISHED","datePublished":"2026-10-19T21:10:11.266Z","dateUpdated":"2026-10-28T15:21:14.748Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-10-19T16:58:51.959Z"},"containers":{"cna":{"title":"Pillow: APNG background disposal allocates full canvas before decompression bomb check","descriptions":[{"lang":"en","value":"Pillow is a Python imaging library. From 8.1.0 until 13.0.0, Pillow can allocate an APNG disposal background at the full canvas size before applying the decompression-bomb check. A crafted APNG with a small first frame, a very large declared canvas, and background disposal or first-frame OP_PREVIOUS reaches PngImageFile._seek while Image.open() positions frame zero. The full-canvas allocation occurs inside Image.open() without requiring pixel loading or frame iteration. This can exhaust memory and deny service. This issue is fixed in version 13.0.0."}],"affected":[{"vendor":"python-pillow","product":"Pillow","versions":[{"version":">= 8.1.0, < 13.0.0","status":"affected"}]}],"references":[{"url":"https://github.com/python-pillow/Pillow/security/advisories/GHSA-5xm2-6676-qcp9","name":"https://github.com/python-pillow/Pillow/security/advisories/GHSA-5xm2-6676-qcp9","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/python-pillow/Pillow/commit/f1acfc54c53502948d0d14121872061df931db48","name":"https://github.com/python-pillow/Pillow/commit/f1acfc54c53502948d0d14121872061df931db48","tags":["x_refsource_MISC"]},{"url":"https://github.com/python-pillow/Pillow/releases/tag/13.0.0","name":"https://github.com/python-pillow/Pillow/releases/tag/13.0.0","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":8.7,"baseSeverity":"HIGH","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","version":"4.0"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-789","lang":"en","description":"CWE-789: Memory Allocation with Excessive Size Value","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-10-19T21:10:11.266Z"},"source":{"advisory":"GHSA-5xm2-6676-qcp9","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/python-pillow/Pillow/security/advisories/GHSA-5xm2-6676-qcp9","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-10-28T15:21:08.274556Z","id":"CVE-2026-112399","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-28T15:21:14.748Z"}}]}}}