Skip to content
OpenAdvisories
High · 7.4 CVE-2026-59825 EUVD-2026-60953

Mastodon: Unwanted deactivation of SSL/TLS certificate verification

Published Aug 18, 2026 · Updated Aug 18, 2026 · Assigned by GitHub_M

Description

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 LDAP_TLS_NO_VERIFY=true, disabling SSL and TLS certificate verification globally for requests made by puma web processes while sidekiq background jobs remain unaffected. This issue is fixed in versions 4.4.19 and 4.5.12.

Affected products

VendorProductAffectedFixed
mastodon mastodon < 4.4.19, >= 4.5.0, < 4.5.12 —

References