Cyber Resilience

CVE-2021-20138

HighPublic PoC

Published: 09 December 2021

Published
09 December 2021
Modified
21 November 2024
KEV Added
—
Patch
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CVSS Score v3.1 8.8 CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0818 92.4th percentile
Risk Priority 23 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-20138 is a high-severity OS Command Injection (CWE-78) vulnerability in Gryphonconnect Gryphon Tower Firmware. Its CVSS base score is 8.8 (High).

Operationally, ranked in the top 7.6% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

An unauthenticated command injection vulnerability exists in multiple parameters in the Gryphon Tower router’s web interface at /cgi-bin/luci/rc. An unauthenticated remote attacker on the same network can execute commands as root on the device by sending a specially crafted malicious…

more

packet to the web interface.

CWE(s)
CWE-78

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

gryphonconnect
gryphon tower firmware
≤ 04.0004.12

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

SC-27 Platform-independent Applications
addresses: CWE-78

Platform-independent apps typically execute inside a managed runtime or sandbox that restricts direct OS command execution, reducing the ability to exploit OS command injection.

SI-10 Information Input Validation
addresses: CWE-78

Validates inputs to block special elements that would alter OS command execution.

References