Misskey
CVE-2021-39169
MEDIUM
Severity by source
AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Lifecycle Timeline
1DescriptionNVD
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.
AnalysisAI
Misskey is a decentralized microblogging platform. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. This Cross-Site Scripting (XSS) vulnerability could allow attackers to inject malicious scripts into web pages viewed by other users.
Technical ContextAI
This vulnerability is classified as Cross-Site Scripting (XSS) (CWE-79), which allows attackers to inject malicious scripts into web pages viewed by other users. 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. Affected products include: Misskey. Version information: prior to 12.51.0.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Sanitize all user input, use Content-Security-Policy headers, encode output contextually (HTML, JS, URL). Use frameworks with built-in XSS protection.
Misskey is an open source, decentralized microblogging platform. Rated high severity (CVSS 7.5), this vulnerability is r
Misskey before 10.102.4 allows hijacking a user's token. Rated medium severity (CVSS 6.1), this vulnerability is remotel
Misskey is an open source, decentralized social media platform. Rated critical severity (CVSS 9.8), this vulnerability i
Misskey is an open source, decentralized social media platform. Rated critical severity (CVSS 9.6), this vulnerability i
Misskey is an open source, federated social media platform. Rated medium severity (CVSS 5.4), this vulnerability is remo
Misskey is an open source, federated social media platform. Rated high severity (CVSS 8.8), this vulnerability is remote
Misskey is an open source, federated social media platform. Rated high severity (CVSS 8.8), this vulnerability is remote
Misskey is an open source, decentralized social media platform with ActivityPub support. Rated high severity (CVSS 8.8),
Misskey is an open source, federated social media platform. Rated high severity (CVSS 8.2), this vulnerability is remote
Misskey is an open source, federated social media platform. Rated high severity (CVSS 8.1), this vulnerability is remote
Misskey is an open source, federated social media platform.
federated social media platform. All Misskey server versions up to 2026.3.1 is affected by improper verification of cryp
Same weakness CWE-79 – Cross-site Scripting (XSS)
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External POC / Exploit Code
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