{"id":"CVE-2026-16477","aliases":["EUVD-2026-108208","GHSA-9gj2-4mhg-73v2"],"status":"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","severity":{"version":"4.0","score":8.4,"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","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00287,"percentile":0.21527,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-502"],"published":"2026-10-22T14:47:26Z","modified":"2026-10-22T19:17:50Z","products":[{"vendor":"mtw","product":"cleanshot x"}],"references":[{"url":"https://cert.pl/en/posts/2026/10/CVE-2026-16477","tags":["third-party-advisory"]},{"url":"https://cleanshot.com/","tags":["product"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-16477"},{"url":"https://cleanshot.com"},{"url":"https://github.com/advisories/GHSA-9gj2-4mhg-73v2"}],"sources":{"cve":[{"id":"CVE-2026-16477","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","status":"published","published":"2026-10-22T14:47:26.652Z","modified":"2026-10-22T19:00:31.571Z","cvss":[{"version":"4.0","score":8.4,"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","level":"high","assessor":"cna"}],"cwes":["CWE-502"],"updated_at":"2026-11-02T14:20:11.24076Z"}],"euvd":[{"id":"EUVD-2026-108208","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","status":"published","published":"2026-10-22T14:47:26Z","modified":"2026-10-22T19:00:31Z","cvss":[{"version":"4.0","score":8.4,"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","level":"high"}],"updated_at":"2026-11-02T16:59:34.021826Z"}],"ghsa":[{"id":"GHSA-9gj2-4mhg-73v2","title":"CleanShot X for macOS insecurely deserializes untrusted data embedded in a .cleanshot project...","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","status":"published","published":"2026-10-22T15:32:50Z","modified":"2026-10-22T15:32:57Z","cvss":[{"version":"4.0","score":8.4,"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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high"}],"cwes":["CWE-502"],"updated_at":"2026-11-02T15:14:16.352322Z"}],"nvd":[{"id":"CVE-2026-16477","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","status":"published","published":"2026-10-22T15:17:05.817Z","modified":"2026-10-22T19:17:50.77Z","cvss":[{"version":"4.0","score":8.4,"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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high","assessor":"secondary"}],"cwes":["CWE-502"],"updated_at":"2026-11-02T14:13:02.724605Z"}]}}