CVE-2023-49105: ownCloud Improper Authentication Vulnerability
Affects ownCloud ownCloudSource CISA KEV
No CVSS score published yet
- Exploitation
Actively exploited – in CISA KEV since 08/27/2026
- KEV deadline
- 08/30/2026
- EPSS
- 43.2% chance of exploitation in 30 days – higher than 98% of CVEs
What to do
CISA 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.
- owncloud.org/security (opens in a new tab)
- owncloud.com/security-advisories/webdav-api-authentication-bypass-using-pre-signed-urls/ (opens in a new tab)
- cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk (opens in a new tab)
- cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2023-49105 (opens in a new tab)
Description
ownCloud contains an improper authentication vulnerability that allows an attacker to access, modify, or delete any file without authentication if the username of a victim is known, and the victim has no signing-key configured.
Weaknesses
References
- owncloud.org/security (opens in a new tab)
- owncloud.com/security-advisories/webdav-api-authentication-bypass-using-pre-signed-urls/ (opens in a new tab)
- cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk (opens in a new tab)
- cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2023-49105 (opens in a new tab)
- cisa.gov/known-exploited-vulnerabilities-catalog?search=CVE-2023-49105 (opens in a new tab)