title: Cross site scripting (XSS) vulnerability using authentication callback in Misskey
description: Misskey is an open source, decentralized social media platform. Due to insufficient validation of the redirect URL during `miauth` authentication in Misskey, arbitrary JavaScript can be executed when a user allows the link. All versions below 13.3.1 (including 12.x) are affected. This has been fixed in version 13.3.1. Users are advised to upgrade. Users unable to upgrade should not allow authentication of untrusted apps.
problem types: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
affected:
{
vendor: misskey-dev
product: misskey
versions:
version: < 13.3.1, status: affected
}
metrics:
cvssV3_1: [
attackComplexity: LOW
attackVector: NETWORK
availabilityImpact: LOW
baseScore: 7.1
baseSeverity: HIGH
confidentialityImpact: LOW
integrityImpact: LOW
privilegesRequired: NONE
scope: CHANGED
userInteraction: REQUIRED
vectorString: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L
version: 3.1
]