Threats / Cisco / CVE-2021-1498
CVE-2021-1498
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-06-16
Cisco HyperFlex HX vulnerability
Cisco HyperFlex HX Installer contains insufficient input validation allowing command execution as the tomcat8 user via OS command injection.
Verdict
Today item — known-exploited.
An unauthenticated or low-privileged attacker can inject arbitrary OS commands through the installer interface, achieving code execution with tomcat8 privileges. Active exploitation in the wild increases risk.
01
Is it exploitable?
— the evidence, ranked above the scoreReported exploitation
4 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03).
Probability (EPSS)
EPSS 0.99999 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Cisco, HyperFlex HX. Confirm exact fixed builds in the vendor advisory.
Weakness (CWE)
Mapped to CWE-78 OS Command Injection — weakness family: Injection.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
02
Who’s exploiting it?
— attribution turns risk into urgencyAttribution not established
No threat-actor attribution is established from the public feed for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.
03
Why it matters
— the attack path, told twice: adversary, then board1
Front door — unauthenticated access narrative 1
Attacker
I craft malicious input containing shell metacharacters to bypass validation in the HyperFlex HX Installer interface.
Business
Attacker gains initial code execution foothold on the installer VM with tomcat8 user privileges.
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
I execute system commands to enumerate the environment, escalate privileges, or establish persistence on the affected device.
Business
Attacker moves laterally within the HyperFlex infrastructure or pivots to connected systems.
3
Lateral reach — past segmentation narrative 3
Attacker
I access or modify HyperFlex configuration, credentials, or cluster data through the compromised installer process.
Business
Attacker gains control over virtualized workloads, storage, or compute resources managed by HyperFlex.
04
What to do
— defensible action- Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05
Coverage & confidence
— what we know, and what we don’tEstablished (cited)
Coverage gaps — stated, not hidden
Disclosure & credit2
Catalogued by ciscoCNA
Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.