CVE-2026-73090 PeerTube: Cross-origin remote video takeover via Update activity

PeerTube is an ActivityPub-federated video streaming platform. Prior to 8.2.2, processUpdateActivity and processUpdateVideo accept an ActivityPub Update containing a Video object without verifying that byActor.url is authorized for the host in videoObject.id, allowing a malicious federated server...

CVE-2026-50128 Mastodon: Spoofing of attribution domains

Mastodon is a free, open-source social network server based on ActivityPub. From 4.3.0 until 4.5.11 and 4.4.18, Mastodon has a feature to let websites credit authors of their articles. To prevent false attribution claims, Mastodon uses the attributionDomains JSON-LD term, however, an error in how...

CVE-2026-50128

Mastodon is a free, open-source social network server based on ActivityPub. From 4.3.0 until 4.5.11 and 4.4.18, Mastodon has a feature to let websites credit authors of their articles. To prevent false attribution claims, Mastodon uses the attributionDomains JSON-LD term, however, an error in how...

PT-2026-52082

Name of the Vulnerable Software and Affected Versions Mastodon versions 4.3.0 through 4.5.10 Mastodon versions 4.4.0 through 4.4.17 Description Mastodon is a free, open-source social network server based on ActivityPub. A flaw in the definition of the attributionDomains JSON-LD term makes Linked...