A newly disclosed vulnerability in the Anti-Virus app for ownCloud 10 shows how even privileged accounts can become an attacker’s best weapon.
Tracked as CVE-2025-53830, the flaw carries a CVSS v3.1 score of 9.1 and stems from a classic Server-Side Request Forgery (SSRF) weakness CWE-918 that lets an authenticated administrator coerce the server into fetching and executing arbitrary remote content.
The bug was reported by security researcher qiushui via YesWeHack and published as GHSA-3wg4-mg27-hj4w by GitHub contributor kw-fscheuer two weeks ago.
While admin-level exploitation requirements cap the severity rating at “high” rather than “critical,” the real-world impact full compromise of confidentiality, integrity, and availability makes this a priority patch for enterprise ownCloud deployments.
The Anti-Virus app integrates with ownCloud 10 to scan uploaded files for malware, typically by connecting to a configured ClamAV or similar scanning daemon. The vulnerability arises because the app fails to properly validate or restrict the destination of outbound requests tied to its scanning configuration.
An attacker with administrative privileges can manipulate this request path to point the server at internal network resources, cloud metadata endpoints, or attacker-controlled infrastructure.
Because the server-side component blindly retrieves and processes the response, this opens the door to loading and executing arbitrary code effectively turning a security scanning feature into a remote code execution vector.
The vector string CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H reveals the mechanics clearly:
- Attack Vector: Network (AV:N), meaning exploitation doesn’t require local access
- Attack Complexity: Low (AC:L), no special conditions needed
- Privileges Required: High (PR:H), the key mitigating factor
- User Interaction: None (UI:N), no victim clicks required
- Scope: Changed (S:C), impact extends beyond the vulnerable component
- Impact: High across confidentiality, integrity, and availability (C:H/I:H/A:H)
That “Scope: Changed” designation is significant it confirms the SSRF can pivot beyond the Anti-Virus app itself into the broader ownCloud environment or connected internal systems.
Affected Versions and Patch Details
Organizations running the following configurations are at risk:
- Anti-Virus for ownCloud app versions prior to 1.2.3
- ownCloud 10 core versions prior to 10.15.3
ownCloud has resolved the issue in both components. Administrators should:
- Upgrade the Anti-Virus app to version 1.2.3 or later
- Upgrade ownCloud 10 core to version 10.15.3 or later
Applying both patches is recommended, since either the app-level fix or the core platform update alone may not fully close the attack surface depending on deployment architecture.
Security teams often deprioritize vulnerabilities that require administrative access, reasoning that a compromised admin account already represents game over.
But this logic overlooks scenarios such as insider threats, compromised admin credentials via phishing, or privilege-escalation chains in which a lower-tier flaw grants attackers just enough access to weaponize this SSRF as a second-stage payload.
Given ownCloud’s widespread use in enterprise file-sharing and its Anti-Virus integration in security-conscious deployments, unpatched instances remain attractive targets, particularly for attackers chaining this SSRF with credential-stuffing or session-hijacking techniques to first obtain admin-level access.
Organizations should treat this as a mandatory patch-cycle item, verify the current Anti-Virus app and core versions immediately, and audit administrative account security as a complementary defense layer.
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