CVE-2026-45156

Nextcloud vulnerable component: User OIDC handling; a missing signature verification allowed an ID4me authority to impersonate any user. Affected versions: 0.3.0–before 3.1.0, 5.0.0–before 5.1.0, and 6.0.0–before 6.4.0. Root cause: absent JWT/signature check in OIDC flow as described in the CVE d...