{"id":"CVE-2026-16477","state":"PUBLISHED","title":"Insecure Deserialization of .cleanshot Files in CleanShot X","description":"CleanShot X for macOS insecurely deserializes untrusted data embedded in a .cleanshot project file (editable screenshot annotations). Exploitation requires an attacker to craft a malicious .cleanshot file, deliver it to the target, and have the target open it; the payload then executes automatically during parsing, resulting in arbitrary code execution in the context of the current user. Users who have never opened a .cleanshot file from an untrusted source are not affected by this vulnerability. This vulnerability was fixed in versions: 4.5.2, 4.6.3, 4.7.8 and 4.8.10","publishedAt":"2026-10-22T14:47:26.652Z","updatedAt":"2026-10-22T19:00:31.571Z","severity":{"score":8.4,"label":"High","version":"4.0","vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L","source":"CERT-PL"},"assigner":"CERT-PL","products":["MTW CleanShot X"],"affected":[{"vendor":"MTW","product":"CleanShot X","defaultStatus":"unaffected","versions":[{"version":"4.0.0","status":"affected","lessThan":"4.5.2","versionType":"semver"},{"version":"4.6.0","status":"affected","lessThan":"4.6.3","versionType":"semver"},{"version":"4.7.0","status":"affected","lessThan":"4.7.8","versionType":"semver"},{"version":"4.8.0","status":"affected","lessThan":"4.8.10","versionType":"semver"}],"platforms":["MacOS"]}],"references":["https://cert.pl/en/posts/2026/10/CVE-2026-16477","https://cleanshot.com/"],"weaknesses":["CWE-502"],"ingestedAt":"2026-10-29T20:11:00.674Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/16xxx/CVE-2026-16477.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-16477","state":"PUBLISHED","datePublished":"2026-10-22T14:47:26.652Z","dateUpdated":"2026-10-22T19:00:31.571Z","assignerShortName":"CERT-PL","assignerOrgId":"4bb8329e-dd38-46c1-aafb-9bf32bcb93c6","dateReserved":"2026-07-21T14:22:56.242Z"},"containers":{"cna":{"title":"Insecure Deserialization of .cleanshot Files in CleanShot X","descriptions":[{"lang":"en","value":"CleanShot X for macOS insecurely deserializes untrusted data embedded in a .cleanshot project file (editable screenshot annotations). 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