CVE-2021-20139
An unauthenticated command injection vulnerability exists in the parameters of operation 3 in the...
An unauthenticated command injection vulnerability exists in the parameters of operation 3 in the controller_server service on Gryphon Tower routers. An unauthenticated remote attacker on the same network can execute commands as root on the device by sending a specially crafted malicious packet to the controller_server service on port 9999.
Attack profile
How easy it is to exploit
- Attack vector
- Adjacent network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
An unauthenticated command injection vulnerability exists in the parameters of operation 3 in the controller_server service on Gryphon Tower routers. An unauthenticated remote attacker on the same network can execute commands as root on the device by sending a specially crafted malicious packet to the controller_server service on port 9999.
- Record
CVE-2021-20139- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 8.3 High
AV:A/AC:L/Au:N/C:C/I:C/A:C - Weakness
- CWE-78
- Updated
- 2026-11-02
CVE List No score
An unauthenticated command injection vulnerability exists in the parameters of operation 3 in the controller_server service on Gryphon Tower routers. An unauthenticated remote attacker on the same network can execute commands as root on the device by sending a specially crafted malicious packet to the controller_server service on port 9999.
- Record
CVE-2021-20139- Updated
- 2026-11-02
EUVDEUVD-2021-7596 No score
An unauthenticated command injection vulnerability exists in the parameters of operation 3 in the controller_server service on Gryphon Tower routers. An unauthenticated remote attacker on the same network can execute commands as root on the device by sending a specially crafted malicious packet to the controller_server service on port 9999.
- Record
EUVD-2021-7596- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-mxxq-jqh7-gv6g No score
An unauthenticated command injection vulnerability exists in the parameters of operation 3 in the...
An unauthenticated command injection vulnerability exists in the parameters of operation 3 in the controller_server service on Gryphon Tower routers. An unauthenticated remote attacker on the same network can execute commands as root on the device by sending a specially crafted malicious packet to the controller_server service on port 9999.
- Record
GHSA-mxxq-jqh7-gv6g- Weakness
- CWE-78
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-20139 is a high vulnerability (CVSS 8.8) in Gryphonconnect Gryphon Tower Firmware, published December 9, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 3.98%, the 90th percentile. No source names a fixed version.