An issue was discovered in ownCloud owncloud/core before 10.13.1. An attacker can access, modify, or delete any file without authentication if the username of a victim is known, and the victim has no signing-key configured. This occurs because pre-signed URLs can be accepted even when no signing-key is configured for the owner of the files. The earliest affected version is 10.6.0.
Description as published by the source, in English.
Key facts
Published
2023-11-21
Last modified
2026-08-28
Assigned by
cve@mitre.org
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Scored by
nvd@nist.gov (NVD Primary)
Probability of exploitation
11.1 %
higher than 95 %
of all known vulnerabilities
EPSS, next 30 days, model v2026.06.15
Fix available
Not registered in the sources
Actively exploited
CISA added this vulnerability to the Known Exploited Vulnerabilities
catalogue on 2026-08-27,
with a remediation deadline of 2026-08-30 for US federal agencies.
Required action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.
Attack techniques
Derived through the weakness type: CVE to CWE to CAPEC to ATT&CK.
This shows which techniques the weakness class is historically used for.
It does not assert that this vulnerability has been exploited that way.
