The files_antivirus component before 1.0.0 for ownCloud mishandles the protection mechanism by which malicious files (that have been upload…

published 2022-01-15 4y ago modified 2026-06-17 4mo ago also EUVD-2021-20503

cvss: 8.8; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 1.2%; EPSS 1.2% chance of exploitation in 30 days, percentile 68%
public exploits: 0; none known

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.

Patch / fix

fixed in 1

owncloud files_antivirus 1.0.0

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Exploit prediction

1.19% chance of exploitation in the next 30 days, higher than 68% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
NVD	3.1	8.8	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	6.5	AV:N/AC:L/Au:S/C:P/I:P/A:P

Classification

Weakness

CWE-434 Unrestricted Upload of File with Dangerous Type

References

doc.owncloud.com /server/admin_manual/release_notes.html
release-notes, vendor-advisory
owncloud.com /security-advisories/cve-2021-33828/
vendor-advisory

Sources

CVE List CVE-2021-33828
NVD CVE-2021-33828

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