CVE-2025-52570 - CVE House
Back to Database
Status published Low CVE-2025-52570

Letmein connection limiter allows an arbitrary amount of simultaneous connections

Vulnerability Description

Letmein is an authenticating port knocker. Prior to version 10.2.1, The connection limiter is implemented incorrectly. It allows an arbitrary amount of simultaneously incoming connections (TCP, UDP and Unix socket) for the services letmeind and letmeinfwd. Therefore, the command line option num-connections is not effective and does not limit the number of simultaneously incoming connections. This issue has been patched in version 10.2.1.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

THREAT MONITOR

Am I Vulnerable?

Launch our assessment wizard to check if your infrastructure is exposed to • CVE-2025-52570

Credits & Attribution

No credits recorded in the NVD database.

References

Affected Vendor

Affected Software

letmein
Vulnerable Versions:
< 10.2.1

Timeline

Official Publish: June 24th, 2025
Last Modified: June 24th, 2025
Added to House: July 22nd, 2026

CVSS Vectors

Weaknesses (CWE)

CWE-799 CWE-770

MITRE ATT&CK TTPs

T1499 Endpoint Denial of Service
Impact
T1498 Network Denial of Service
Impact
T1190 Exploit Public-Facing Application
Initial Access
T1562 Impair Defenses
Defense Evasion
T1046 Network Service Discovery
Discovery