How severe is CVE-2025-52570?

CVE-2025-52570 has a CVSS 4.0 base score of 1.7, rated low severity.

Is CVE-2025-52570 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (25th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2025-52570?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2025-52570 have an EU (EUVD) identifier?

Yes. CVE-2025-52570 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-19032.

When was CVE-2025-52570 published?

CVE-2025-52570 was published on 2025-06-24 and last updated on 2026-06-17.

CVE-2025-52570

CVE-2025-52570 is a low-severity vulnerability with a CVSS 4.0 base score of 1.7. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-770.

Key facts

Severity: Low (CVSS 4.0 base score 1.7)
EPSS exploit prediction: 0% (25th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-19032
Weakness: CWE-770
Published: 2025-06-24
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2025-52570?: 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.
How severe is CVE-2025-52570?: CVE-2025-52570 has a CVSS 4.0 base score of 1.7, rated low severity.
Is CVE-2025-52570 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (25th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2025-52570?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-52570 have an EU (EUVD) identifier?: Yes. CVE-2025-52570 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-19032.
When was CVE-2025-52570 published?: CVE-2025-52570 was published on 2025-06-24 and last updated on 2026-06-17.

References

Other CWE-770 (Allocation of Resources Without Limits or Throttling) vulnerabilities

CVE-2026-31283 — Critical (CVSS 9.8): In Totara LMS v19.1.5 and before, the forgot password API does not implement rate limiting for the target email…
CVE-2020-37067 — Critical (CVSS 9.8): Filetto 1.0 FTP server contains a denial of service vulnerability in the FEAT command processing that allows attackers…
CVE-2021-47875 — Critical (CVSS 9.8): GeoGebra CAS Calculator 6.0.631.0 contains a denial of service vulnerability that allows attackers to crash the…
CVE-2025-11832 — Critical (CVSS 9.8): Allocation of Resources Without Limits or Throttling vulnerability in Azure Access Technology BLU-IC2, Azure Access…
CVE-2024-44241 — Critical (CVSS 9.8): The issue was addressed with improved bounds checks. This issue is fixed in iOS 18.1 and iPadOS 18.1, macOS Sequoia…
CVE-2022-3439 — Critical (CVSS 9.8): Allocation of Resources Without Limits or Throttling in GitHub repository ikus060/rdiffweb prior to 2.5.0.

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