Cyber Resilience

CVE-2021-45456

RCE in Apache Kylin 4.0.0

High EPSSRCECommand Injection
Published
06 January 2022
Modified
21 November 2024
Patch / advisory
View advisory
CVSS Score v3.1 9.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.89 99.8th percentile
Risk Priority 97 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2021-45456 is a critical-severity Command Injection (CWE-77) vulnerability in Apache Kylin. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked in the top 0.2% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

OWASP Top 10 for Web (2025)

A05:2025 Injection

EU & UK References

Vulnerability Data

Apache kylin checks the legitimacy of the project before executing some commands with the project name passed in by the user. There is a mismatch between what is being checked and what is being used as the shell command argument…

more

in DiagnosisService. This may cause an illegal project name to pass the check and perform the following steps, resulting in a command injection vulnerability. This issue affects Apache Kylin 4.0.0.

CWE(s)
CWE-77

Related Threats

MITRE ATT&CK Enterprise Techniques

T1059 Command and Scripting Interpreter Execution
Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1059.001 PowerShell Execution
Adversaries may abuse PowerShell commands and scripts for execution.
attack.mitre.org →
T1059.003 Windows Command Shell Execution
Adversaries may abuse the Windows command shell for execution.
attack.mitre.org →
T1059.004 Unix Shell Execution
Adversaries may abuse Unix shell commands and scripts for execution.
attack.mitre.org →
T1059.008 Network Device CLI Execution
Adversaries may abuse scripting or built-in command line interpreters (CLI) on network devices to execute malicious command and payloads.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2020-1956Same product: Apache Kylin
CVE-2026-62392Same product: Apache Kylin
CVE-2022-24697Same product: Apache Kylin
CVE-2025-30067Same product: Apache Kylin
CVE-2025-61735Same product: Apache Kylin
CVE-2024-48944Same product: Apache Kylin
CVE-2022-43396Same product: Apache Kylin
CVE-2026-62390Same product: Apache Kylin
CVE-2025-61733Same product: Apache Kylin
CVE-2025-61734Same product: Apache Kylin

Affected Assets

apache
kylin
4.0.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V1.2.3
  • V1.2.5
  • V1.2.8
  • V1.2.9

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly require input validation and neutralization that prevent command injection.

DE.CM-09 partial match
prevents

Runtime monitoring of software and data can detect anomalous command execution resulting from injection.

ID.RA-01 partial match
prevents

Identifying recorded vulnerabilities enables remediation of command-injection flaws before exploitation.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.28 Secure coding mostly match
prevents

Secure coding standards require proper escaping and parameterization of commands, directly eliminating CWE-77.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing in development catches command-injection vulnerabilities before release.

A.8.25 Secure development life cycle partial match
prevents

Secure development life cycle mandates input validation and command construction practices that directly prevent command injection.

A.8.26 Application security requirements partial match
prevents

Application security requirements explicitly call for controls against injection flaws including command injection.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure architecture principles reduce the attack surface but do not prescribe the specific neutralization techniques needed.

References