CVE-2025-52570

Letmein connection limiter allows an arbitrary amount of simultaneous connections

State: Published
Severity: 1.7 Low
Published: Jun 24, 2025
Updated: Jun 24, 2025
Reserved: Jun 18, 2025

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.

Scores

CVSS	Score	Vector	Source
4.0	1.7 Low	CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U	GitHub_M

Weaknesses

CWE-799 Improper Control of Interaction Frequency
CWE-770 Allocation of Resources Without Limits or Throttling

Affected Products

Product	Versions
letmeinmbuesch	< 10.2.1Affected

References

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