CVE-2025-52570
Low
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.
SeverityLow
CVSS1.7
Exploit probability—
ProductMbuesch Letmein
PublishedJun 24, 2025
First seenJun 24, 2025
How to fix
Sources list no fixed version or patch link for this vulnerability.
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mbuesch letmein | < 10.2.1 | — |
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