CVE-2021-25309

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-03-02 · updated 2026-06-17
Weakness: CWE-307

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.

Affected products

Gigaset Dx600A Firmware: v41.00-175

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/
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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