CVE-2023-49105: ownCloud Improper Authentication Vulnerability

CISA Known Exploited Vulnerabilities

Name

ownCloud Improper Authentication Vulnerability

Vendor

ownCloud

Product

ownCloud

Added to the catalog

2026-08-27

Due date for US federal agencies

2026-08-30

Weaknesses

CWE-287

Catalog version

2026.10.30

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.

Required action (CISA)

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.

Ransomware use: CISA does not mark known use of this vulnerability in ransomware campaigns.

Links in CISA's notes

• https://owncloud.org/security
• https://owncloud.com/security-advisories/webdav-api-authentication-bypass-using-pre-signed-urls/
• https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk
• https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk
• https://nvd.nist.gov/vuln/detail/CVE-2023-49105

Read on 2026-11-02T23:39:54.475Z under licence cisa-kev-cc0@b0067899 from https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json

NVD analysis

Status

Analyzed

Published

2023-11-21T22:15:08.613

Last modified

2026-08-28T12:21:09.753

Weaknesses

CWE-287

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.

References

• https://owncloud.com/security-advisories/webdav-api-authentication-bypass-using-pre-signed-urls/ (Vendor Advisory)
• https://owncloud.org/security (Product)
• https://owncloud.com/security-advisories/webdav-api-authentication-bypass-using-pre-signed-urls/ (Vendor Advisory)
• https://owncloud.org/security (Product)
• https://hunt.io/blog/chinese-speaking-operator-philippine-nuclear-naval-contractor (Third Party Advisory)
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-49105 (US Government Resource)

This product uses the NVD API but is not endorsed or certified by the NVD.

Read on 2026-11-02T23:42:08.214Z under licence nvd-api-terms-of-use@ff2a5288 from https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2023-49105

CVE record

Assigner

mitre

State

PUBLISHED

Published

2023-11-21T00:00:00.000Z

Updated

2026-08-28T03:55:23.877Z

Problem types

n/a

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.

References

• https://owncloud.org/security
• https://owncloud.com/security-advisories/webdav-api-authentication-bypass-using-pre-signed-urls/

Read on 2026-11-03T02:05:04.202Z under licence cve-terms-of-use@81bfa2f3 from https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2023/49xxx/CVE-2023-49105.json

Defensive techniques (MITRE D3FEND)

D3FEND maps these defensive techniques to the weakness (CWE) that NVD lists for this CVE, through the digital artifacts the weakness affects. D3FEND does not say they stop this vulnerability.

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