# CVE-2023-49105: ownCloud Improper Authentication Vulnerability

> CVE-2023-49105: ownCloud Improper Authentication Vulnerability. CVSS 9.8 (CVSS 3.1), in CISA KEV.

Canonical: https://rewindex.com/cve/CVE-2023-49105
Last updated: 2026-08-28T12:21:09Z

- Published: 2023-11-21 00:00 UTC · Updated: 2026-08-28 12:21 UTC · Assigner: mitre
- CVSS: 9.8 (CVSS 3.1) · Severity: Critical · Vector: CVSS:3.1/AC:L/AV:N/A:H/C:H/I:H/PR:N/S:U/UI:N
- EPSS: 43.2%, 99th percentile (scored 2026-10-25)
- CISA KEV: yes, added 2026-08-27, federal due date 2026-08-30, ransomware use: Unknown

## 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.

## 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.

## Affected vendors and products

- ownCloud: ownCloud

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2023-49105)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2023-49105)
- [https://owncloud.com/security-advisories/webdav-api-authentication-bypass-using-pre-signed-urls/](https://owncloud.com/security-advisories/webdav-api-authentication-bypass-using-pre-signed-urls/)
- [https://owncloud.org/security](https://owncloud.org/security)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2023-49105 · Markdown: https://rewindex.com/cve/CVE-2023-49105.md · JSON: https://rewindex.com/api/v1/cves/CVE-2023-49105 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T03:12:20.601Z