CVE-2026-63100
Maybe through 0.6.0 contains a missing authorization vulnerability that allows authenticated low-privilege member-role users to access and modify global hosting settings by exploiting unprotected show and update actions in the Settings::HostingsController, where the before_action ensure_admin filter is applied only to the clear_cache action. Attackers can read the operator's Synth API key rendered in plaintext via a form field value attribute, overwrite it with an attacker-controlled value, toggle public registration settings, and disable email confirmation requirements to disrupt the entire instance.
No public exploitation has been reported so far. No distribution fix is listed yet; apply vendor mitigations and monitor.
Recommended action: Track your distribution's security tracker and apply the fix as soon as it ships.
Severity metrics
CVSS 4.0 : 7.1 HIGH · CVSS 3.1 : 6.5 MEDIUM
Vector: AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
Affected & fixed versions by distribution
Versions are the native distribution strings (backport-aware): RHEL/Debian/SUSE backport fixes, so compare with the distro version comparator (dpkg / rpm / vercmp), not the upstream version.
No affected package in the tracked watchlist yet (Debian, Ubuntu, Arch, SUSE, Red Hat...). Triage may still be pending.