Letmein · Letmein · CVE-2025-52570
Name of the Vulnerable Software and Affected Versions:
Letmein versions prior to 10.2.1
Description:
The connection limiter in Letmein is implemented incorrectly, allowing an arbitrary amount of simultaneously incoming connections for the services letmeind and letmeinfwd. This makes the command line option num-connections ineffective, and it does not limit the number of simultaneously incoming connections. The issue can lead to a Possible Denial Of Service by resource exhaustion.
Recommendations:
For versions prior to 10.2.1, upgrade to version 10.2.1 to resolve the issue.
As a temporary workaround, consider limiting the number of active connections to the letmeind port via firewall or restricting the resource consumption of the service with a service manager such as systemd.