CVE & CISA-KEV Catalog

CVE-2021-4406

CRITICAL
9.1
CVSS v3
NVD

Description

An authenticated attacker is able to create alerts that trigger a stored XSS attack. POC * go to the alert manager * open the ITSM tab * add a webhook with the URL/service token value ' -h && id | tee /tmp/ttttttddddssss #' (whitespaces are tab characters) * click add * click apply * create a test alert * The test alert will run the command “id | tee /tmp/ttttttddddssss” as root. * after the test alert inspect /tmp/ttttttddddssss it'll contain the ids of the root user.

CWE-77Command Injection

How to fix

Remediation Available
quantastorNVD
Affected:< 6.0.0.355Fixed in:6.0.0.355CVE-2021-4406derived from NVD

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredHigh
User InteractionNone
ScopeChanged

Impact

ConfidentialityHigh
IntegrityHigh
AvailabilityHigh

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H

Exploit Intelligence

0.78%probability of exploitation in 30 days
51stpercentile

Moderate risk: more likely to be exploited than 51% of all known CVEs.

References

Third-Party Advisory1
Product1

Related Vulnerabilities

Other CWE-77 (Command Injection) vulnerabilities, ordered by exploit likelihood. View all

CVESeverityCVSSEPSSExploitedFix
CVE-2024-3400Critical10.0100%KEV + Ransom-
CVE-2024-21887Critical9.1100%KEV + Ransom-
CVE-2023-1671Critical9.8100%KEVFix
CVE-2023-1389High8.8100%KEVFix
CVE-2021-1498Critical9.8100%KEVFix
CVE-2012-1823Critical9.8100%KEVFix
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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2025-09-24.