CVE-2025-52570 (GCVE-0-2025-52570)

Vulnerability from cvelistv5 – Published: 2025-06-24 03:13 – Updated: 2025-06-24 14:42
VLAI
Title
Letmein connection limiter allows an arbitrary amount of simultaneous connections
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.
Severity
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
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-06-24 14:41 UTC
CWE
  • CWE-799 - Improper Control of Interaction Frequency
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
References
Impacted products
Vendor Product Version CPE status
mbuesch letmein Affected: < 10.2.1
guessed Create a notification for this product.
Show details on NVD website
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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