CVE-2023-36459: Mastodon is a free, open-source social network server based on ActivityPub. Starting in version 1.3 and prior to versions 3.5.9, 4.0.5, and 4.1.3, an attacker…

PriorityP427medium6.1CVSS 3.1

AVNACLPRNUIRSCCLILAN

EPSS

1.09%

61.3th percentile

Mastodon is a free, open-source social network server based on ActivityPub. Starting in version 1.3 and prior to versions 3.5.9, 4.0.5, and 4.1.3, an attacker using carefully crafted oEmbed data can bypass the HTML sanitization performed by Mastodon and include arbitrary HTML in oEmbed preview cards. This introduces a vector for cross-site scripting (XSS) payloads that can be rendered in the user's browser when a preview card for a malicious link is clicked through. Versions 3.5.9, 4.0.5, and 4.1.3 contain a patch for this issue.

Affected

6 ranges

Vendor	Product	Version range	Fixed in
joinmastodon	mastodon	>= 1.3 < 3.5.9	3.5.9
joinmastodon	mastodon	>= 4.0.0 < 4.0.5	4.0.5
joinmastodon	mastodon	>= 4.1.0 < 4.1.3	4.1.3
mastodon	mastodon	—	—
mastodon	mastodon	—	—
mastodon	mastodon	—	—

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