CVE-2021-33191Network attack vector

Host command execution via mutable C2 update command

Published Aug 24, 2021 · Updated Aug 3, 2024

Command injection in Apache NiFi MiNiFi C++ 0.5.0 through versions before 0.10.0 allows remote attackers to execute host commands through C2. The agent-update handler executes a configured patch command after c2-update messages can replace its trusted binary value with an arbitrary command. Reachability requires an enabled C2 channel, and successful commands run with the MiNiFi agent process's privileges.

CVSS severity9.8
Critical
EPSS probability4.02%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Command injection in Apache NiFi MiNiFi C++ 0.5.0 through versions before 0.10.0 allows remote attackers to execute host commands through C2. The agent-update handler executes a configured patch command after c2-update messages can replace its trusted binary value with an arbitrary command. Reachability requires an enabled C2 channel, and successful commands run with the MiNiFi agent process's privileges.

The record

CVE
CVE-2021-33191
Published
Aug 24, 2021
Updated
Aug 3, 2024
Vendor
The Apache Software Foundation
Product
Apache NiFi MiNiFi C++
Classifications
CWE-78, T1059
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 24, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0.5.0 <Apache NiFi - MiNiFi C++* changes=[{"at":"0.10.0","status":"unaffected"}]

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Apache Software Foundation · Apache NiFi MiNiFi C++version=0.5.0 <Apache NiFi - MiNiFi C++* changes=[{"at":"0.10.0","status":"unaffected"}]

Published CVSS scores

9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.5NIST NVDAV:N/AC:L/Au:N/C:P/I:P/A:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
T1059Command and Scripting Interpreter

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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