Cyber Resilience

CVE-2021-1498

CriticalCISA KEVActive ExploitationEUVD ExploitedPublic PoCRCE

Published: 06 May 2021

Published
06 May 2021
Modified
28 October 2025
KEV Added
03 November 2021
Patch
CVSS Score v3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.9421 99.9th percentile
Risk Priority 96 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-1498 is a critical-severity OS Command Injection (CWE-78) vulnerability in Cisco Hyperflex Hx Data Platform. Its CVSS base score is 9.8 (Critical).

Operationally, ranked in the top 0.1% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified are NIST 800-53 AC-3 (Access Enforcement) and SI-10 (Information Input Validation).

Deeper analysis

CVE-2021-1498 is a set of command injection vulnerabilities, tracked under CWE-78 and CWE-77, that affect the web-based management interface of Cisco HyperFlex HX. The flaws permit unauthenticated remote attackers to inject and execute arbitrary commands on affected devices, reflected in the maximum CVSS 3.1 base score of 9.8.

An unauthenticated attacker with network access can send specially crafted HTTP requests to the management interface and obtain full command execution, resulting in complete compromise of confidentiality, integrity, and availability without any user interaction.

The Cisco Security Advisory cisco-sa-hyperflex-rce-TjjNrkpR provides remediation guidance and patch information, while the vulnerability is also listed in the CISA Known Exploited Vulnerabilities catalog. Public exploit code demonstrating remote command execution has been published on Packet Storm.

EU & UK References

Vulnerability details

Multiple vulnerabilities in the web-based management interface of Cisco HyperFlex HX could allow an unauthenticated, remote attacker to perform command injection attacks against an affected device. For more information about these vulnerabilities, see the Details section of this advisory.

CWE(s)
KEV Date Added
03 November 2021

Related Threats

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

Affected Assets

cisco
hyperflex hx data platform
≤ 4.0\(2e\) · 4.5 — 4.5\(2a\)

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

prevent

Enforces authentication and authorization on the HyperFlex web management interface so that unauthenticated remote attackers cannot reach the command-injection entry points.

prevent

Requires validation and sanitization of all HTTP input fields that the CVE exploits for command injection (CWE-78/77).

AC-17 Remote Access partial match
prevent

Restricts remote network access to the management interface, reducing the attack surface that allows unauthenticated command execution.

References