{"cve":"CVE-2021-39169","nvd":{"published":"2021-08-27T13:15:07.020","modified":"2026-06-17T04:03:14.330","status":"Modified","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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","score":5.4},"cwes":["CWE-79"],"references":["https://github.com/misskey-dev/misskey/commit/ec203f7f795766f76b55fecc9248168c1cdf6c99","https://github.com/misskey-dev/misskey/security/advisories/GHSA-pmmv-jwqh-f5ww","https://github.com/misskey-dev/misskey/commit/ec203f7f795766f76b55fecc9248168c1cdf6c99","https://github.com/misskey-dev/misskey/security/advisories/GHSA-pmmv-jwqh-f5ww"],"products":["misskey:misskey"],"source":"nvd","synced_at":"2026-10-19T21:21:57.125947417+00:00"},"epss":{"cve":"CVE-2021-39169","score":0.00736,"percentile":0.54471,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}