Siemens SINEC NMS Flaw Allows Arbitrary Password Resets

The National Vulnerability Database (NVD) has flagged a critical authorization bypass vulnerability, CVE-2026-25654, affecting Siemens SINEC NMS versions prior to V4.0 SP3. This flaw, rated with a CVSS score of 8.8 (HIGH), stems from insufficient validation of user authorization during password reset requests.

According to the NVD, this oversight could allow an authenticated remote attacker to sidestep authorization checks entirely. The upshot? An attacker could then reset the password of any arbitrary user account within the SINEC NMS environment. This is a classic authorization bypass scenario, tracked as CWE-639, and it’s a nasty one because it essentially hands over the keys to the kingdom.