CVE-2026-9780

Quest NetVault Backup addclient3 Cross-Site Scripting Authentication Bypass Vulnerability

HIGH
8.8
CVSS Score
Published: June 24, 2026 at 11:13 PM UTC
Updated: October 25, 2026 at 11:10 PM UTC
1 product affected across 1 vendorNetVault Backup

Using NetVault Backup by Quest?

Get instant alerts when new vulnerabilities affect NetVault Backup - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
HIGH8.8
Exploit prediction
EPSS 0.9%
SSVC
No known exploit

Description

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

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 14.0.214.0.1.7
Affected range stops below 14.0.2, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (2)

SSVC — Action Prioritization

SSVCNo known exploitNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.8HIGHzdi
Vector?

Quick Info

StatusANALYZED
CWE
CWE-79

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card