{"id":"CVE-2021-39169","aliases":["EUVD-2021-25571","GHSA-pmmv-jwqh-f5ww"],"status":"published","title":"XSS vulnerability using dialog","description":"Misskey is a decentralized microblogging platform. In versions of Misskey prior to 12.51.0, malicious actors can use the web client built-in dialog to display a malicious string, leading to cross-site scripting (XSS). XSS could compromise the API request token. This issue has been fixed in version 12.51.0. There are no known workarounds aside from upgrading.","severity":{"version":"3.1","score":8,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00736,"percentile":0.54955,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-79"],"published":"2021-08-27T12:40:09Z","modified":"2026-10-20T10:54:53Z","products":[{"vendor":"misskey","product":"misskey"},{"vendor":"misskey-dev","product":"misskey"}],"references":[{"url":"https://github.com/misskey-dev/misskey/security/advisories/GHSA-pmmv-jwqh-f5ww","tags":["x_refsource_CONFIRM","x_transferred","Patch","Third Party Advisory","fix"]},{"url":"https://github.com/misskey-dev/misskey/commit/ec203f7f795766f76b55fecc9248168c1cdf6c99","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix"]}],"sources":{"cve":[{"id":"CVE-2021-39169","title":"XSS vulnerability using dialog","description":"Misskey is a decentralized microblogging platform. In versions of Misskey prior to 12.51.0, malicious actors can use the web client built-in dialog to display a malicious string, leading to cross-site scripting (XSS). XSS could compromise the API request token. This issue has been fixed in version 12.51.0. There are no known workarounds aside from upgrading.","status":"published","published":"2021-08-27T12:40:09Z","modified":"2024-08-04T01:58:18.216Z","cvss":[{"version":"3.1","score":8,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H","level":"high","assessor":"cna"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:33:09.540052Z"}],"euvd":[{"id":"EUVD-2021-25571","description":"Misskey is a decentralized microblogging platform. In versions of Misskey prior to 12.51.0, malicious actors can use the web client built-in dialog to display a malicious string, leading to cross-site scripting (XSS). XSS could compromise the API request token. This issue has been fixed in version 12.51.0. There are no known workarounds aside from upgrading.","status":"published","published":"2021-08-27T12:40:09Z","modified":"2024-08-04T01:58:18Z","cvss":[{"version":"3.1","score":8,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-03T03:24:23.719378Z"}],"nvd":[{"id":"CVE-2021-39169","description":"Misskey is a decentralized microblogging platform. In versions of Misskey prior to 12.51.0, malicious actors can use the web client built-in dialog to display a malicious string, leading to cross-site scripting (XSS). XSS could compromise the API request token. This issue has been fixed in version 12.51.0. There are no known workarounds aside from upgrading.","status":"published","published":"2021-08-27T13:15:07.02Z","modified":"2026-06-17T04:03:14.33Z","cvss":[{"version":"3.1","score":8,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H","level":"high","assessor":"secondary"},{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"primary"},{"version":"2.0","score":3.5,"vector":"AV:N/AC:M/Au:S/C:N/I:P/A:N","level":"low","assessor":"primary"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:06:57.67549Z"}],"osv":[{"id":"CVE-2021-39169","description":"Misskey is a decentralized microblogging platform. In versions of Misskey prior to 12.51.0, malicious actors can use the web client built-in dialog to display a malicious string, leading to cross-site scripting (XSS). XSS could compromise the API request token. This issue has been fixed in version 12.51.0. There are no known workarounds aside from upgrading.","status":"published","published":"2021-08-27T13:15:07.02Z","modified":"2026-10-20T10:54:53.30698837Z","cvss":[{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:44:20.843843Z"}]}}