CVE-2026-41657
MediumWhat is CVE-2026-41657?
Admidio is an open-source user management solution. Prior to version 5.0.9, the contacts_data.php endpoint uses a weaker permission check (isAdministratorUsers(), requiring only rol_edit_user=true) than the frontend UI (contacts.php) which correctly requires the stronger isAdministrator() (requiring rol_administrator=true) and the contacts_show_all system setting. A user manager who is not a full administrator can directly request contacts_data.php?mem_show_filter=3 to retrieve all user records across all organizations in the Admidio instance, bypassing multi-tenant organization isolation. This issue has been patched in version 5.0.9.
CVSS Vector Breakdown
CVSS 3.1Exploitable remotely over the network without requiring access to the local system.
No special conditions required. Exploit can be performed reliably and repeatedly.
Administrative or root-level privileges required to exploit.
No user interaction required. Exploit runs without any victim action.
Exploiting the vulnerability only affects the vulnerable component itself.
Complete loss of confidentiality. All data on the component may be exposed.
No integrity impact. Data cannot be modified.
No availability impact. Service remains fully operational.
FAQ
CVE-2026-41657 has a CVSS score of 4.9/10, rated as Medium. Review the affected products list and apply vendor patches.
CVSS (Common Vulnerability Scoring System) rates vulnerability severity from 0.0 to 10.0. CVE-2026-41657 scores 4.9/10 (Medium). Scores 9.0–10.0 are Critical, 7.0–8.9 are High, 4.0–6.9 are Medium, and below 4.0 are Low.
The list of devices confirmed to be affected by CVE-2026-41657 is shown in the "Affected Devices" section above. Check your firmware version against the vendor security advisory and apply the latest patch.
Apply the latest firmware or software update from the vendor. Check the References section above for official advisories and patch notes. If no patch is available, consider disabling the affected feature or isolating the device from untrusted networks.