ZDI-26-369: Quest NetVault Backup addclient3 Cross-Site Scripting Authentication Bypass Vulnerability
A cross-site scripting vulnerability in the addclient3 webpage of Quest NetVault Backup allows remote attackers to bypass authentication. Exploitation requires user interaction, such as visiting a malicious page or opening a malicious file. The vulnerability stems from improper validation of user-supplied data, enabling script injection. This flaw can be combined with other vulnerabilities to execute arbitrary code with SYSTEM privileges. Quest has issued an update to address this issue.
AI Analysis
Technical Summary
CVE-2026-9780 is a remote authentication bypass vulnerability in Quest NetVault Backup's addclient3 webpage caused by insufficient validation of user input, leading to cross-site scripting. An attacker can exploit this by tricking a user into interacting with malicious content, potentially allowing arbitrary code execution in the SYSTEM context when combined with other vulnerabilities. Quest has released an update to fix this vulnerability.
Potential Impact
Successful exploitation allows remote attackers to bypass authentication mechanisms, potentially leading to full system compromise via arbitrary code execution with SYSTEM privileges. User interaction is required for exploitation. The vulnerability affects confidentiality, integrity, and availability of the affected system.
Mitigation Recommendations
Quest has issued an official update that corrects this vulnerability. Applying the vendor-provided patch is the recommended remediation. No additional mitigation steps are specified or required beyond applying the update.
ZDI-26-369: Quest NetVault Backup addclient3 Cross-Site Scripting Authentication Bypass Vulnerability
Description
A cross-site scripting vulnerability in the addclient3 webpage of Quest NetVault Backup allows remote attackers to bypass authentication. Exploitation requires user interaction, such as visiting a malicious page or opening a malicious file. The vulnerability stems from improper validation of user-supplied data, enabling script injection. This flaw can be combined with other vulnerabilities to execute arbitrary code with SYSTEM privileges. Quest has issued an update to address this issue.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-9780 is a remote authentication bypass vulnerability in Quest NetVault Backup's addclient3 webpage caused by insufficient validation of user input, leading to cross-site scripting. An attacker can exploit this by tricking a user into interacting with malicious content, potentially allowing arbitrary code execution in the SYSTEM context when combined with other vulnerabilities. Quest has released an update to fix this vulnerability.
Potential Impact
Successful exploitation allows remote attackers to bypass authentication mechanisms, potentially leading to full system compromise via arbitrary code execution with SYSTEM privileges. User interaction is required for exploitation. The vulnerability affects confidentiality, integrity, and availability of the affected system.
Mitigation Recommendations
Quest has issued an official update that corrects this vulnerability. Applying the vendor-provided patch is the recommended remediation. No additional mitigation steps are specified or required beyond applying the update.
Technical Details
- Article Source
- {"url":"http://www.zerodayinitiative.com/advisories/ZDI-26-369/","fetched":true,"fetchedAt":"2026-06-24T22:25:04.280Z","wordCount":207}
Threat ID: 6a3c59a24853345fc1ee9674
Added to database: 06/24/2026, 22:26:42 UTC
Last enriched: 06/24/2026, 22:27:58 UTC
Last updated: 06/24/2026, 23:46:06 UTC
Views: 3
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