Adjacent-network username enumeration
Published Sep 14, 2021 · Updated Apr 23, 2025
Improper request-rate control in Siemens SINEMA Remote Connect Server before 3.0 SP2 allows remote attackers to enumerate usernames. Siemens identifies username brute forcing as the flaw but does not disclose the affected endpoint or the response behavior that distinguishes valid accounts. The attacker must reach the server from the same network without authentication; the documented consequence is disclosure of valid usernames only.
Summary
What happened
Improper request-rate control in Siemens SINEMA Remote Connect Server before 3.0 SP2 allows remote attackers to enumerate usernames. Siemens identifies username brute forcing as the flaw but does not disclose the affected endpoint or the response behavior that distinguishes valid accounts. The attacker must reach the server from the same network without authentication; the documented consequence is disclosure of valid usernames only.
The record
- CVE
- CVE-2021-37191
- Published
- Sep 14, 2021
- Updated
- Apr 23, 2025
- Vendor
- Siemens
- Product
- SINEMA Remote Connect Server
- Classifications
- CWE-799, T1087
- Attack vector
- adjacent
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 14, 2021CVE publishedPublication date reported by the CVE source.
- Apr 23, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=All versions < V3.0 SP2
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo