CVE-2026-25540

Mastodon is a free, open-source social network server based on ActivityPub. Prior to versions 4.3.19, 4.4.13, 4.5.6, Mastodon is vulnerable to web cache poisoning via Rails.cache. When AUTHORIZEDFETCH is enabled, the ActivityPub endpoints for pinned posts and featured hashtags have contents that...

CVE-2026-25540

Mastodon is a free, open-source social network server based on ActivityPub. Prior to versions 4.3.19, 4.4.13, 4.5.6, Mastodon is vulnerable to web cache poisoning via Rails.cache. When AUTHORIZEDFETCH is enabled, the ActivityPub endpoints for pinned posts and featured hashtags have contents that...

EUVD-2026-5329

Mastodon is a free, open-source social network server based on ActivityPub. Prior to versions 4.3.19, 4.4.13, 4.5.6, Mastodon is vulnerable to web cache poisoning via Rails.cache. When AUTHORIZEDFETCH is enabled, the ActivityPub endpoints for pinned posts and featured hashtags have contents that...

CVE-2026-25540

Mastodon prior to versions 4.3.19, 4.4.13, and 4.5.6 is vulnerable to web cache poisoning in Rails.cache when AUTHORIZED_FETCH is enabled. The ActivityPub endpoints for pinned posts and featured hashtags cache responses that depend on the signer’s account, but the internal cache reuse does not re...

CVE-2026-25540 Mastodon's signature-dependent ActivityPub collection responses cached under signature-independent keys (Web Cache Poisoning via `Rails.cache`)

Mastodon is a free, open-source social network server based on ActivityPub. Prior to versions 4.3.19, 4.4.13, 4.5.6, Mastodon is vulnerable to web cache poisoning via Rails.cache. When AUTHORIZEDFETCH is enabled, the ActivityPub endpoints for pinned posts and featured hashtags have contents that...

CVE-2026-25540 Mastodon's signature-dependent ActivityPub collection responses cached under signature-independent keys (Web Cache Poisoning via `Rails.cache`)

Mastodon is a free, open-source social network server based on ActivityPub. Prior to versions 4.3.19, 4.4.13, 4.5.6, Mastodon is vulnerable to web cache poisoning via Rails.cache. When AUTHORIZEDFETCH is enabled, the ActivityPub endpoints for pinned posts and featured hashtags have contents that...

Mastodon 安全漏洞

Mastodon is an open-source social networking server based on ActivityPub. Versions of Mastodon prior to 4.3.19, 4.4.13, and 4.5.6 have security vulnerabilities. These vulnerabilities stem from web cache poisoning, which may lead to incorrect reuse of cached content...

PT-2026-6319

Name of the Vulnerable Software and Affected Versions Mastodon versions prior to 4.3.19 Mastodon versions prior to 4.4.13 Mastodon versions prior to 4.5.6 Description Mastodon, a free, open-source social network server based on ActivityPub, contains a flaw related to web cache poisoning. When the...

BIT-MASTODON-2026-23963 Mastodon missing length limits on list names, filter names, and filter keywords

Mastodon is a free, open-source social network server based on ActivityPub. Prior to versions 4.5.5, 4.4.12, and 4.3.18, the server does not enforce a maximum length for the names of lists or filters, or for filter keywords, allowing any user to set an arbitrarily long string as the name or...

BIT-MASTODON-2026-23962 Mastodon vulnerable to Denial of Service from a single post (client/server)

Mastodon is a free, open-source social network server based on ActivityPub. Mastodon versions before v4.3.18, v4.4.12, and v4.5.5 do not have a limit on the maximum number of poll options for remote posts, allowing attackers to create polls with a very large amount of options, greatly increasing...

BIT-MASTODON-2026-23961 Mastodon may allow a remote suspension bypass

Mastodon is a free, open-source social network server based on ActivityPub. Mastodon allows server administrators to suspend remote users to prevent interactions. However, some logic errors allow already-known posts from such suspended users to appear in timelines if boosted. Furthermore, under...

PT-2026-6340

Mastodon is a free, open-source social network server based on ActivityPub. Mastodon versions before v4.3.18, v4.4.12, and v4.5.5 do not have a limit on the maximum number of poll options for remote posts, allowing attackers to create polls with a very large amount of options, greatly increasing...

PT-2026-6339

Mastodon is a free, open-source social network server based on ActivityPub. Mastodon allows server administrators to suspend remote users to prevent interactions. However, some logic errors allow already-known posts from such suspended users to appear in timelines if boosted. Furthermore, under...

PT-2026-6341

Mastodon is a free, open-source social network server based on ActivityPub. Prior to versions 4.5.5, 4.4.12, and 4.3.18, the server does not enforce a maximum length for the names of lists or filters, or for filter keywords, allowing any user to set an arbitrarily long string as the name or...

BIT-MASTODON-2026-23964 Mastodon has insufficient access control to push notification settings

Mastodon is a free, open-source social network server based on ActivityPub. Prior to versions 4.5.5, 4.4.12, and 4.3.18, an insecure direct object reference in the web push subscription update endpoint lets any authenticated user update another user's push subscription by guessing or obtaining th...

CVE-2026-23456

creationtimestamp| type| source ---|---|--- 2026-01-26 19:15:08+00:00| seen| https://mastodon.social/ap/users/115426718704364579/statuses/115962996812609233 2026-01-26 19:15:32+00:00| seen| https://bsky.app/profile/netsecio.bsky.social/post/3mddxeewicc2o 2026-02-18 08:12:01+00:00| seen|...

CVE-2026-12345

creationtimestamp| type| source ---|---|--- 2026-01-26 19:15:04+00:00| seen| https://mastodon.social/ap/users/115426718704364579/statuses/115962996504160664 2026-01-26 19:15:23+00:00| seen| https://bsky.app/profile/netsecio.bsky.social/post/3mddxe3xemk2j 2026-03-13 06:38:31+00:00| seen|...

CVE-2026-23963

Mastodon is a free, open-source social network server based on ActivityPub. Prior to versions 4.5.5, 4.4.12, and 4.3.18, the server does not enforce a maximum length for the names of lists or filters, or for filter keywords, allowing any user to set an arbitrarily long string as the name or...

CVE-2026-23961

Mastodon is a free, open-source social network server based on ActivityPub. Mastodon allows server administrators to suspend remote users to prevent interactions. However, some logic errors allow already-known posts from such suspended users to appear in timelines if boosted. Furthermore, under...

CVE-2026-23964

Mastodon is a free, open-source social network server based on ActivityPub. Prior to versions 4.5.5, 4.4.12, and 4.3.18, an insecure direct object reference in the web push subscription update endpoint lets any authenticated user update another user's push subscription by guessing or obtaining th...