CVE-2016-5876 Owncloud CVE debrief

Who should care

Administrators and security teams running ownCloud server deployments, especially instances with the gallery app enabled and any environment still on affected pre-8.2.6 or pre-9.0.3 releases.

Technical summary

According to the CVE description, ownCloud server versions before 8.2.6 and 9.x before 9.0.3 are affected when the gallery app is enabled. The attacker can trigger direct requests to download arbitrary images. NVD maps the issue to CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N and CWE-264.

Defensive priority

Medium. The issue is network-reachable and can expose image confidentiality, but the published CVSS indicates high attack complexity and no integrity or availability impact.

Recommended defensive actions

• Upgrade ownCloud server to a fixed release at or above 8.2.6 or 9.0.3.
• Review whether the gallery app is enabled anywhere in production and disable it where it is not needed.
• Confirm affected instances against the NVD version criteria and the vendor advisory before scheduling remediation.
• After upgrading, verify that direct image download requests are no longer accepted for unauthorized access patterns.

Evidence notes

The CVE description states: ownCloud server before 8.2.6 and 9.x before 9.0.3, when the gallery app is enabled, allows remote attackers to download arbitrary images via a direct request. NVD reference data includes the ownCloud vendor advisory and a SecurityFocus BID entry. NVD CPE criteria enumerate affected ownCloud versions up to 8.2.5 and specific 9.0.0, 9.0.1, and 9.0.2 releases.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.