{"id":"CVE-2026-47251","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-47251","generatedAt":"2026-10-28T02:13:43.600Z","title":"The fix for CVE-2026-3949 (commit `b97c8b5`, PR #1712) introduced an integer overflow in the very security check it added.","description":"libheif is a HEIF and AVIF file format decoder and encoder. The fix for CVE-2026-3949 (commit `b97c8b5`, PR #1712) introduced an integer overflow in the very security check it added. The check itself can be bypassed, allowing a crafted HEIF file with a VVC track to trigger the same out-of-bounds heap read that CVE-2026-3949 was meant to prevent. This is a separate, currently-unpatched vulnerability. Issue #1712 was closed as fixed without testing the edge case where `size` is near `UINT32_MAX`. Version 1.22.0 patches the issue.","published":"2026-07-21T22:17:13.000Z","lastModified":"2026-10-24T19:10:00.000Z","status":"Analyzed","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"4.0","score":6.8,"severity":"MEDIUM","vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M"},"cwe":["CWE-125","CWE-190"],"affected":["struktur/libheif"],"epss":{"score":0.00159,"percentile":0.04988,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.16%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://github.com/strukturag/libheif/issues/1712","tags":["Issue Tracking"],"source":"security-advisories@github.com"},{"url":"https://github.com/strukturag/libheif/security/advisories/GHSA-p6q9-fhf2-vj9v","tags":["Exploit","Vendor Advisory"],"source":"security-advisories@github.com"},{"url":"https://github.com/strukturag/libheif/issues/1712","tags":["Issue Tracking"],"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"},{"url":"https://github.com/strukturag/libheif/security/advisories/GHSA-p6q9-fhf2-vj9v","tags":["Exploit","Vendor Advisory"],"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-47251","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}