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CVE-2025-52570GHSA-JPV7-P47H-F43J

Letmein connection limiter allows an arbitrary amount of simultaneous connections

Published
Last modified
published
Not listed in CISA KEV
Fix
Fixed in 10.2.1
None on Exploit-DB, Metasploit or GitHub
  • Exploitation: none
  • Automatable: no
  • Technical impact: partial

Summary

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.

Timeline

  1. CVE published
  2. CISA SSVC assessment

    Exploitation: none · Automatable: no · Technical impact: partial

  3. Record last updated

Affected versions

  • mbuesch letmein

    fixed in 10.2.1

  • letmeindcrates.io

    fixed in 10.2.1

  • letmeinfwdcrates.io

    fixed in 10.2.1

References 2

GitHub · mbuesch/letmein