CVE-2026-9780: Quest NetVault Backup addclient3 Cross-Site Scripting Authentication Bypass Vulnerability

Published Jun 24, 2026
·
Updated

Quest NetVault Backup addclient3 Cross-Site Scripting Authentication Bypass Vulnerability. This vulnerability allows remote attackers to bypass authentication on affected installations of Quest NetVault Backup. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file.

The specific flaw exists within the addclient3 webpage. The issue results from the lack of proper validation of user-supplied data, which can lead to the injection of an arbitrary script. An attacker can leverage this in conjunction with other vulnerabilities to execute arbitrary code in the context of SYSTEM. Was ZDI-CAN-27666.

Affected Software

2 affected components
Quest NetVault Backup
Quest NetVault Backup<14.0.2

Event History

Jun 24, 2026
CVE Published
via MITRE·11:13 PM
Data Sourced
via MITRE·11:13 PM
DescriptionSeverityWeakness
Jun 25, 2026
Data Sourced
via NVD·12:17 AM
DescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2026-9780?

CVE-2026-9780 has a high severity rating of 8.8.

2

How do I fix CVE-2026-9780?

To fix CVE-2026-9780, it's essential to apply the latest security patches provided by Quest for NetVault Backup.

3

What types of attacks can CVE-2026-9780 facilitate?

CVE-2026-9780 can facilitate Cross-Site Scripting (XSS) attacks that allow remote attackers to bypass authentication.

4

What software is affected by CVE-2026-9780?

CVE-2026-9780 affects Quest NetVault Backup installations.

5

Is user interaction required to exploit CVE-2026-9780?

Yes, user interaction is required as the target must visit a malicious site to exploit CVE-2026-9780.

Contact

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