CVE-2026-11420

Two path traversal vulnerabilities in the Network Installation Service (NIS) of Altium Enterprise Server allow an unauthenticated network attacker to write arbitrary files to any writable location on the server filesystem and to read package archive files from the server. No authentication, session, or credentials are required. Because content-controlled files can be written to web-accessible directories, or used to overwrite application binaries or configuration files, exploitation can be escalated to remote code execution in the context of the service account, and can disclose deployment package contents. Altium 365 cloud deployments are not affected, as the Network Installation Service is not part of the cloud offering.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://www.altium.com/platform/security-compliance/security-advisories	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:altium:on-prem_enterprise_server:*:*:*:*:*:*:*:*

History

16 Jun 2026, 20:49

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 9.8
First Time		Altium Altium on-prem Enterprise Server
References	~~() https://www.altium.com/platform/security-compliance/security-advisories -~~	() https://www.altium.com/platform/security-compliance/security-advisories - Vendor Advisory
CPE		cpe:2.3:a:altium:on-prem_enterprise_server::::::::

05 Jun 2026, 20:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-05 20:17

Updated : 2026-06-16 20:49

NVD link : CVE-2026-11420

Mitre link : CVE-2026-11420

CVE.ORG link : CVE-2026-11420

JSON object : View

Products Affected

altium

on-prem_enterprise_server

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

CWE-306

Missing Authentication for Critical Function

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