Skip to content
OpenAdvisories

Vendor

mastodon

46 known vulnerabilities.

16 results · Clear filters · Feed

  • High 7.4

    Mastodon: Unwanted deactivation of SSL/TLS certificate verification

    Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.4.19 and from 4.5.0 until 4.5.12, Mastodon's app/models/concerns/user/ldap_authenticable.rb mutates OpenSSL::SSL::SSLContext::DEFAULT_PARAMS when LDAP authentication uses L…

  • High 7.5

    Mastodon: Personally-identifying information disclosure due to incorrect access control validation

    Mastodon is a free, open-source social network server based on ActivityPub. From 4.6.0-beta.1 until 4.6.4 and 4.7.0-beta.1, any logged-in local user could use the show action in app/controllers/admin/collections_controller.rb to access personally identifying …

  • High 7.5

    Mastodon: Exhausting data by an unauthenticated request to the admin retention API

    Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.4.21, 4.5.14, 4.6.4, and 4.7.0-beta.1, the administrative statistics endpoints handled by Api::V1::Admin::MeasuresController and Api::V1::Admin::RetentionController checked…

  • High 7.5

    Mastodon: Persistent anonymous DoS via unhandled NoMethodError in MATH_TRANSFORMER

    Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.5.11, 4.4.18, and 4.3.24, a DoS can be triggered by (Uncaught Exception vulerability), due to missing exception handling in the math sanitizer. Malformed <math> nodes can r…

  • High 8.6

    Mastodon: SSRF protection bypass on older Ruby versions

    Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.5.10, 4.4.17, and 4.3.23, when using Ruby versions older than 3.4, PrivateAddressCheck.private_address? returns false for IPv4-mapped IPv6 addresses (::ffff:a.b.c.d) corres…

  • High 8.7

    Mastodon: SSRF Bypass via IPv6 Unspecified Address (::)

    Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.5.10, 4.4.17, and 4.3.23, the list of disallowed IP address ranges was lacking an IP address range that can be used to reach local IP addresses. An attacker can use an IP a…

  • High 7.5
    CVE-2026-47777 Public exploit

    Mastodon has a consent-check bypass in its remote Collections

    Mastodon is a free, open-source social network server based on ActivityPub. In versions there is a missing condition in the check if remote accounts consented to be featured in a remote Collection could lead to attackers bypassing the check and faking consent…

  • High 8.2

    Mastodon: Insufficient verification of email addresses

    Mastodon is a free, open-source social network server based on ActivityPub. Prior to v4.5.9, v4.4.16, and v4.3.22, Mastodon allows restricting new user sign-up based on e-mail domain names, and performs basic validation on e-mail addresses, but fails to restr…

  • High 7.5

    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 …

  • High 7.1

    Mastodon has SSRF Protection bypass

    Mastodon is a free, open-source social network server based on ActivityPub. By nature, Mastodon performs a lot of outbound requests to user-provided domains. Mastodon, however, has some protection mechanism to disallow requests to local IP addresses (unless s…

  • High 8.2

    Mastodon has improper authorship check on audience extension for existing posts

    Mastodon is a self-hosted, federated microblogging platform. Starting in version 2.6.0 and prior to versions 4.1.18 and 4.2.10, by crafting specific activities, an attacker can extend the audience of a post they do not own to other Mastodon users on a target …

  • High 8.5

    Lack of media type verification of Activity Streams objects allows impersonation of remote accounts

    Mastodon is a free, open-source social network server based on ActivityPub. Prior to versions 4.2.7, 4.1.15, 4.0.15, and 3.5.19, when fetching remote statuses, Mastodon doesn't check that the response from the remote server has a `Content-Type` header value o…

  • High 7.4

    Mastodon Invalid Domain Name Normalization vulnerability

    Mastodon is a free, open-source social network server based on ActivityPub. Prior to versions 3.5.14, 4.0.10, 4.1.8, and 4.2.0-rc2, under certain circumstances, attackers can exploit a flaw in domain name normalization to spoof domains they do not own. Versio…

  • High 7.5

    Mastodon vulnerable to Denial of Service through slow HTTP responses

    Mastodon is a free, open-source social network server based on ActivityPub. When performing outgoing HTTP queries, Mastodon sets a timeout on individual read operations. Prior to versions 3.5.9, 4.0.5, and 4.1.3, a malicious server can indefinitely extend the…

  • High 7.7

    Mastodon's blind LDAP injection in login allows the attacker to leak arbitrary attributes from LDAP database

    Mastodon is a free, open-source social network server based on ActivityPub Mastodon allows configuration of LDAP for authentication. Starting in version 2.5.0 and prior to versions 3.5.8, 4.0.4, and 4.1.2, the LDAP query made during login is insecure and the …

  • High 7.4
    CVE-2022-0432 Scanner template

    Prototype Pollution in mastodon/mastodon

    Prototype Pollution in GitHub repository mastodon/mastodon prior to 3.5.0.