How severe is CVE-2021-25306?

CVE-2021-25306 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-25306 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-25306?

CVE-2021-25306 affects Gigaset Dx600a Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-25306?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-25306 published?

CVE-2021-25306 was published on 2021-03-02 and last updated on 2026-06-17.

CVE-2021-25306

CVE-2021-25306 is a high-severity vulnerability in Gigaset Dx600a Firmware with a CVSS 3.x base score of 7.5. 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-120.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 7.8
EPSS exploit prediction: 1% (71st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-120
Affected product: Gigaset Dx600a Firmware
Published: 2021-03-02
Last modified: 2026-06-17

Description

A buffer overflow vulnerability in the AT command interface of Gigaset DX600A v41.00-175 devices allows remote attackers to force a device reboot by sending relatively long AT commands.

Frequently asked questions

What is CVE-2021-25306?: A buffer overflow vulnerability in the AT command interface of Gigaset DX600A v41.00-175 devices allows remote attackers to force a device reboot by sending relatively long AT commands.
How severe is CVE-2021-25306?: CVE-2021-25306 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-25306 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-25306?: CVE-2021-25306 affects Gigaset Dx600a Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-25306?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-25306 published?: CVE-2021-25306 was published on 2021-03-02 and last updated on 2026-06-17.

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/

Affected products (1)

cpe:2.3:o:gigaset:dx600a_firmware:v41.00-175:*:*:*:*:*:*:*

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