CVE-2021-33827Network attack vector

Admin-level code execution via command-option injection

Published Jan 15, 2022 · Updated Aug 3, 2024

OS command injection in ownCloud files_antivirus before 1.0.0 allows remote authenticated users to execute arbitrary server code. SettingsController accepted web-supplied ClamAV executable paths and command options and persisted them for later process execution without shell-safe restrictions. Administrative access is required; injected commands run with the ownCloud server process's privileges, enabling data access, modification, or service interruption.

CVSS severity6.6
Medium
EPSS probability2.09%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

OS command injection in ownCloud files_antivirus before 1.0.0 allows remote authenticated users to execute arbitrary server code. SettingsController accepted web-supplied ClamAV executable paths and command options and persisted them for later process execution without shell-safe restrictions. Administrative access is required; injected commands run with the ownCloud server process's privileges, enabling data access, modification, or service interruption.

The record

CVE
CVE-2021-33827
Published
Jan 15, 2022
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-78, CAPEC-88, T1059
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Jan 15, 2022CVE 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.2NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
6.6ownCloudCVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:L
9.0NVDAV:N/AC:L/Au:S/C:C/I:C/A:C

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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
CAPEC-88OS 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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