CVE-2026-9780Network attack vector

Authentication bypass via addclient3 script injection

Published Jun 24, 2026 · Updated Jun 24, 2026

Cross-site scripting in Quest NetVault Backup 14.0.1.7 allows remote attackers to bypass authentication through the addclient3 webpage. The page accepts user-supplied data without proper validation, allowing that data to inject an arbitrary script. Exploitation requires a target to visit a malicious page or open a malicious file; chaining can execute code as SYSTEM.

CVSS severity8.8
High
EPSS probability0.94%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in Quest NetVault Backup 14.0.1.7 allows remote attackers to bypass authentication through the addclient3 webpage. The page accepts user-supplied data without proper validation, allowing that data to inject an arbitrary script. Exploitation requires a target to visit a malicious page or open a malicious file; chaining can execute code as SYSTEM.

The record

CVE
CVE-2026-9780
Published
Jun 24, 2026
Updated
Jun 24, 2026
Vendor
Quest Software
Product
NetVault Backup
Classifications
CWE-79, T1189
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 24, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 24, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=14.0.1.7

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Quest Software · NetVault Backupversion=14.0.1.7

Published CVSS scores

8.8Zero Day InitiativeCVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1189Drive-by Compromise

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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