CVE entry · CVE-2023-49105
CVE-2023-49105: ownCloud Improper Authentication Vulnerability
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.
- Actively exploited: added to CISA’s KEV catalog on August 27, 2026.
- Use by ransomware: not established so far.
- Remediation deadline for US federal agencies: August 30, 2026.
Description from CISA’s KEV catalog.
What to do
- Check whether your estate includes ownCloud, including internet-facing devices.
- Apply the vendor’s patch or mitigations (references below). Failing that, isolate the product or stop using it, as CISA requires of US federal agencies.
- An exploited vulnerability has often been used before it was fixed: look for signs of compromise, especially on internet-facing devices.
References
- Vendor advisory or reference cited by CISA (owncloud.org)
- Vendor advisory or reference cited by CISA (owncloud.com)
- NVD entry (NIST)
- CISA KEV catalog