CVE-2026-11423Network attack vector

Authenticated administrator takeover via filename path traversal

Published Jun 5, 2026 · Updated Jun 5, 2026

Path traversal in Altium On-Prem Enterprise Server before 8.1.1 allows remote authenticated users to read arbitrary server files. The MCAD and Simulation download flows construct a filesystem path from a filename in a collaboration message without validating that the result remains inside the intended directory. Regular workspace access is sufficient to read the master configuration, obtain privileged account credentials, and authenticate as a system administrator.

CVSS severity9.4
Critical
EPSS probability0.32%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Path traversal in Altium On-Prem Enterprise Server before 8.1.1 allows remote authenticated users to read arbitrary server files. The MCAD and Simulation download flows construct a filesystem path from a filename in a collaboration message without validating that the result remains inside the intended directory. Regular workspace access is sufficient to read the master configuration, obtain privileged account credentials, and authenticate as a system administrator.

The record

CVE
CVE-2026-11423
Published
Jun 5, 2026
Updated
Jun 5, 2026
Vendor
Altium
Product
Altium On-Prem Enterprise Server
Classifications
CWE-22, CAPEC-126, CAPEC-233, T1552.001, T1068
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 5, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 5, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=0 <8.1.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Altium · Altium On-Prem Enterprise Serverversion=0 <8.1.1

Published CVSS scores

9.4AltiumCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA: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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
CAPEC-126Path Traversal
CAPEC-233Privilege Escalation
T1552.001Credentials In Files
T1068Exploitation for Privilege Escalation

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

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo