CVE-2025-40736: Siemens SINEC NMS · Missing Authentication
Affects Siemens SINEC NMSSource CVE Database V5
Not known to be exploited · CVSS 9.8 Critical.
Data as of 26 Oct 2026, 09:15 UTC
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 39% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 8 Jul 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Siemens SINEC NMS | Affected
| Fixed in– |
AI-suggested
Given the lack of an official patch at the time of this report, European organizations should implement the following specific mitigations: 1) Restrict network access to the SINEC NMS management interface by implementing strict firewall rules and network segmentation to limit exposure only to trusted administrative hosts. 2) Deploy intrusion detection and prevention systems (IDS/IPS) with signatures or anomaly detection tuned to identify unauthorized access attempts or unusual administrative credential changes. 3) Enforce multi-factor authentication (MFA) at network perimeter points and for any indirect access to the management system to add layers of defense, even if the application itself lacks authentication on the vulnerable endpoint. 4) Monitor logs and audit trails for any suspicious activity related to administrative credential changes or access patterns. 5) Engage with Siemens support channels to obtain updates on patch availability and apply patches immediately upon release. 6) Consider temporary compensating controls such as disabling or restricting the vulnerable endpoint if feasible, or deploying web application firewalls (WAF) with custom rules to block unauthorized requests targeting the credential modification function. 7) Conduct regular security assessments and penetration tests focused on the SINEC NMS environment to identify and remediate any additional weaknesses.
Description
A vulnerability has been identified in SINEC NMS (All versions < V4.0). The affected application exposes an endpoint that allows an unauthorized modification of administrative credentials. This could allow an unauthenticated attacker to reset the superadmin password and gain full control of the application (ZDI-CAN-26569).