CVE-2023-49105
Critical 9.8 Exploited in the wild (KEV)
Confirmed active exploitation — CISA KEV catalog
- Name
- ownCloud Improper Authentication Vulnerability
- Added to catalog
- Remediation due date (US federal)
- 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.
Description
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.
Metrics
- CVSS 3.1
-
9.8 (CRITICAL)
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 43% (percentile: 99) as of 2 November 2026
- CWE
- CWE-287
Affected products
owncloud: owncloud server
References
- https://owncloud.com/security-advisories/webdav-api-authentication-bypass-using… Vendor Advisory
- https://owncloud.com/security-advisories/webdav-api-authentication-bypass-using… Vendor Advisory
- https://owncloud.org/security Product
- https://owncloud.org/security Product
- https://hunt.io/blog/chinese-speaking-operator-philippine-nuclear-naval-contrac… Third Party Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023… US Government Resource