CVE-2021-39169

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.

Category

8.0
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.36%
Third-Party Advisory github.com Third-Party Advisory github.com
Affected: misskey-dev misskey
Published at:
Updated at:

References

Link Tags
https://github.com/misskey-dev/misskey/security/advisories/GHSA-pmmv-jwqh-f5ww third party advisory patch
https://github.com/misskey-dev/misskey/commit/ec203f7f795766f76b55fecc9248168c1cdf6c99 third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-39169?
CVE-2021-39169 has been scored as a high severity vulnerability.
How to fix CVE-2021-39169?
To fix CVE-2021-39169, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-39169 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-39169 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-39169?
CVE-2021-39169 affects misskey-dev misskey.
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