mbuesch letmein up to 10.2.0 letmeind/letmeinfwd improper control of interaction frequency

CVSS Meta Temp Score
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CTI Interest Score
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5.1$0-$5k0.00

Summaryinfo

A vulnerability labeled as problematic has been found in mbuesch letmein up to 10.2.0. Affected is an unknown function of the component letmeind/letmeinfwd. Executing a manipulation can lead to improper control of interaction frequency. This vulnerability appears as CVE-2025-52570. The attack may be performed from remote. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability has been found in mbuesch letmein up to 10.2.0 and classified as problematic. This vulnerability affects an unknown part of the component letmeind/letmeinfwd. The manipulation with an unknown input leads to a improper control of interaction frequency vulnerability. The CWE definition for the vulnerability is CWE-799. The product does not properly limit the number or frequency of interactions that it has with an actor, such as the number of incoming requests. As an impact it is known to affect availability. CVE summarizes:

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.

The advisory is shared for download at github.com. This vulnerability was named CVE-2025-52570 since 06/18/2025. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available.

Upgrading to version 10.2.1 eliminates this vulnerability. Applying the patch 43207cd77580410d97165d1e3c07361ba6f3558c is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2025-19032). Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔍
CNA CVSS-BT Score: 🔍
CNA Vector: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Improper control of interaction frequency
CWE: CWE-799 / CWE-400 / CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: letmein 10.2.1
Patch: 43207cd77580410d97165d1e3c07361ba6f3558c

Timelineinfo

06/18/2025 🔍
06/24/2025 +6 days 🔍
06/24/2025 +0 days 🔍
06/27/2025 +3 days 🔍

Sourcesinfo

Product: github.com

Advisory: GHSA-jpv7-p47h-f43j
Status: Confirmed

CVE: CVE-2025-52570 (🔍)
GCVE (CVE): GCVE-0-2025-52570
GCVE (VulDB): GCVE-100-313708
EUVD: 🔍

Entryinfo

Created: 06/24/2025 08:06
Updated: 06/27/2025 06:49
Changes: 06/24/2025 08:06 (70), 06/24/2025 10:42 (1), 06/24/2025 18:24 (1), 06/27/2025 06:49 (1)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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