ZDI-26-369: Quest NetVault Backup addclient3 Cross-Site Scripting Authentication Bypass Vulnerability
CVE-2026-9780 is a vulnerability in Quest NetVault Backup's addclient3 webpage that allows remote attackers to bypass authentication by injecting arbitrary scripts due to improper validation of user-supplied data. Exploitation requires user interaction, such as visiting a malicious page or opening a malicious file. The vulnerability can be leveraged with other flaws to execute arbitrary code with SYSTEM privileges. Quest has issued an update to address this issue.
AI Analysis
Technical Summary
This vulnerability in Quest NetVault Backup affects the addclient3 webpage, where insufficient validation of user input allows injection of arbitrary scripts. This flaw enables remote attackers to bypass authentication if the target interacts with malicious content. The vulnerability has a CVSS rating of 8.8 assigned by ZDI and can lead to full system compromise when combined with other vulnerabilities. Quest has released an update to fix this issue.
Potential Impact
Successful exploitation allows remote attackers to bypass authentication and potentially execute arbitrary code with SYSTEM privileges on affected Quest NetVault Backup installations. This compromises confidentiality, integrity, and availability of the system.
Mitigation Recommendations
Quest has issued an official update to correct this vulnerability. Applying the vendor's update is the recommended remediation. No additional mitigation steps are specified or required beyond installing the official fix.
ZDI-26-369: Quest NetVault Backup addclient3 Cross-Site Scripting Authentication Bypass Vulnerability
Description
CVE-2026-9780 is a vulnerability in Quest NetVault Backup's addclient3 webpage that allows remote attackers to bypass authentication by injecting arbitrary scripts due to improper validation of user-supplied data. Exploitation requires user interaction, such as visiting a malicious page or opening a malicious file. The vulnerability can be leveraged with other flaws 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
This vulnerability in Quest NetVault Backup affects the addclient3 webpage, where insufficient validation of user input allows injection of arbitrary scripts. This flaw enables remote attackers to bypass authentication if the target interacts with malicious content. The vulnerability has a CVSS rating of 8.8 assigned by ZDI and can lead to full system compromise when combined with other vulnerabilities. Quest has released an update to fix this issue.
Potential Impact
Successful exploitation allows remote attackers to bypass authentication and potentially execute arbitrary code with SYSTEM privileges on affected Quest NetVault Backup installations. This compromises confidentiality, integrity, and availability of the system.
Mitigation Recommendations
Quest has issued an official update to correct this vulnerability. Applying the vendor's update is the recommended remediation. No additional mitigation steps are specified or required beyond installing the official fix.
Technical Details
- Article Source
- {"url":"http://www.zerodayinitiative.com/advisories/ZDI-26-369/","fetched":true,"fetchedAt":"2026-06-24T22:25:04.280Z","wordCount":207}
- Classification
- {"confidence":0.95,"severitySource":"heuristic","classifier":"rss-v2"}
Threat ID: 6a3c59a24853345fc1ee9674
Added to database: 06/24/2026, 22:26:42 UTC
Last enriched: 07/23/2026, 23:13:38 UTC
Last updated: 08/09/2026, 00:41:16 UTC
Views: 98
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