Mastodon's verified profile links can be formatted in a misleading way
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 5.4epss 0.6%
exploitation probability
0.6%top 54% of all CVEs
observed exploitation
nono source reports it
Mastodon is a free, open-source social network server based on ActivityPub. Starting in version 2.6.0 and prior to versions 3.5.9, 4.0.5, and 4.1.3, an attacker can craft a verified profile link using specific formatting to conceal arbitrary parts of the link, enabling it to appear to link to a different URL altogether. The link is visually misleading, but clicking on it will reveal the actual link. This can still be used for phishing, though, similar to IDN homograph attacks. Versions 3.5.9, 4.0.5, and 4.1.3 contain a patch for this issue.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
Affected products
mastodon · mastodonReferences
https://github.com/mastodon/mastodon/commit/610731b03dfcadd887078cb0399f4e514aa1931chttps://github.com/mastodon/mastodon/releases/tag/v3.5.9https://github.com/mastodon/mastodon/releases/tag/v4.0.5https://github.com/mastodon/mastodon/releases/tag/v4.1.3https://github.com/mastodon/mastodon/security/advisories/GHSA-55j9-c3mp-6fcq