10.0
CRITICAL CVSS 4.0
CVE-2026-11420
Path Traversal in Altium Enterprise Server NIS Allows Unauthenticated Arbitrary File Write and File Read
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.

INFO

Published Date :

June 5, 2026, 8:17 p.m.

Last Modified :

June 5, 2026, 8:49 p.m.

Remotely Exploit :

Yes !

Source :

4760f414-e1ae-4ff1-bdad-c7a9c3538b79
Affected Products

The following products are affected by CVE-2026-11420 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 4.0 CRITICAL 4760f414-e1ae-4ff1-bdad-c7a9c3538b79
CVSS 4.0 CRITICAL 4760f414-e1ae-4ff1-bdad-c7a9c3538b79
Solution
Apply vendor updates to fix file write and read vulnerabilities.
  • Update to the latest version provided by the vendor.
  • Restrict network access to the NIS service.
  • Monitor file system for unauthorized changes.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-11420.

URL Resource
https://www.altium.com/platform/security-compliance/security-advisories
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-11420 is associated with the following CWEs:

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-11420 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-11420 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by 4760f414-e1ae-4ff1-bdad-c7a9c3538b79

    Jun. 05, 2026

    Action Type Old Value New Value
    Added 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.
    Added CVSS V4.0 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
    Added CWE CWE-22
    Added CWE CWE-306
    Added Reference https://www.altium.com/platform/security-compliance/security-advisories
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.