CVE-2023-49105
Published: 21 November 2023
Summary
CVE-2023-49105 is a critical-severity Improper Authentication (CWE-287) vulnerability in Owncloud Owncloud Server. Its CVSS base score is 9.8 (Critical).
Operationally, ranked in the top 0.4% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
Deeper analysis
CVE-2023-49105 is an authentication bypass vulnerability in ownCloud owncloud/core versions before 10.13.1, first affecting the 10.6.0 release. It stems from improper handling of pre-signed URLs under CWE-287, allowing acceptance of such URLs even when the file owner has no signing-key configured. The flaw carries a CVSS 3.1 score of 9.8.
An unauthenticated attacker who knows a victim's username can exploit the issue over the network to access, modify, or delete arbitrary files belonging to that user. No user interaction or privileges are required, and the attack succeeds specifically against accounts lacking a signing-key.
ownCloud security advisories recommend upgrading to version 10.13.1 or later; the patches address acceptance of pre-signed URLs when no signing-key is present. Administrators should also review the linked advisories at owncloud.com and owncloud.org for configuration guidance on signing-keys.
The EPSS score sits at a high 0.8961 with no subsequent rise indicated.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2023-53114
Vulnerability details
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…
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can be accepted even when no signing-key is configured for the owner of the files. The earliest affected version is 10.6.0.
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Detects unauthorized successful logons resulting from improper authentication implementations.
Documented procedures ensure personnel are trained on authentication mechanisms, tangibly lowering the risk of improper authentication being exploited.
Security awareness training instructs users on secure authentication practices and avoiding credential compromise.
Training on authentication mechanisms and best practices decreases the occurrence of improper authentication.
Non-repudiation requires strong authentication mechanisms to irrefutably attribute performed actions to specific individuals or processes.
Session content review can reveal authentication bypasses or failures in session establishment.
Review of authentication-related audit records can detect improper authentication mechanisms or bypasses.
Assessments check authentication mechanisms for correct implementation and effectiveness, reducing successful authentication bypass attempts.