CVE-2026-11420

CRITICAL EPSS 48.8%

Published Jun 5, 20263w ago · Modified Jun 17, 20261w ago

10.0 CVSS 4.0

Critical

Published Jun 5, 2026 3w ago

Last Modified Jun 17, 2026 1w ago

Description

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 Details

Base Score

10.0

Exploitability

—

Impact

—

Vector string

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Attack Vector Network

Attack Complexity Low

Privileges Required None

User Interaction None

Scope X

Threat Intelligence

EPSS Exploit Probability

48.8% percentile

Exploit & Patch Status

No Known Exploit

No Patch Available

Weaknesses 2

CWE-22 Path Traversal Resource Mgmt

CWE-306 Missing Authentication for Critical Function Authentication

Affected Products 1

Vendor	Product	Version	Range
altium	on-prem_enterprise_server	*	<8.1.1

References 1

altium.com https://www.altium.com/platform/security-compliance/security-advisories

Vendor Advisory

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.