How severe is CVE-2021-33828?

CVE-2021-33828 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-33828 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-33828?

CVE-2021-33828 affects Owncloud Files Antivirus. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-33828?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-33828 published?

CVE-2021-33828 was published on 2022-01-15 and last updated on 2026-06-17.

CVE-2021-33828

CVE-2021-33828 is a high-severity vulnerability in Owncloud Files Antivirus with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-434.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.5
EPSS exploit prediction: 1% (63rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-434
Affected product: Owncloud Files Antivirus
Published: 2022-01-15
Last modified: 2026-06-17

Description

The files_antivirus component before 1.0.0 for ownCloud mishandles the protection mechanism by which malicious files (that have been uploaded to a public share) are supposed to be deleted upon detection.

Frequently asked questions

What is CVE-2021-33828?: The files_antivirus component before 1.0.0 for ownCloud mishandles the protection mechanism by which malicious files (that have been uploaded to a public share) are supposed to be deleted upon detection.
How severe is CVE-2021-33828?: CVE-2021-33828 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-33828 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-33828?: CVE-2021-33828 affects Owncloud Files Antivirus. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-33828?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-33828 published?: CVE-2021-33828 was published on 2022-01-15 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:owncloud:files_antivirus:*:*:*:*:*:*:*:*

More vulnerabilities in Owncloud Files Antivirus

CVE-2021-33827 — High (CVSS 7.2): The files_antivirus component before 1.0.0 for ownCloud allows OS Command Injection via the administration settings.
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