CVE-2021-25309
CVE-2021-25309 is a critical-severity vulnerability in Gigaset Dx600a Firmware with a CVSS 3.x base score of 9.8. 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-307.
Key facts
- Severity: Critical (CVSS 3.x base score 9.8)
- CVSS v2: 5.0
- EPSS exploit prediction: 1% (68th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-307
- Affected product: Gigaset Dx600a Firmware
- Published:
- Last modified:
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.
Frequently asked questions
- What is 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 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.
- How severe is CVE-2021-25309?
- CVE-2021-25309 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-25309 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-25309?
- CVE-2021-25309 affects Gigaset Dx600a Firmware. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-25309?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2021-25309 published?
- CVE-2021-25309 was published on 2021-03-02 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:o:gigaset:dx600a_firmware:v41.00-175:*:*:*:*:*:*:*
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