CVE-2026-11420CWE-22CWE-306

Path Traversal in Altium Enterprise Server NIS Allows Unauthenticated Arbitrary File Write and File Read

Critical · published June 5, 2026

CVSS v4.0
10.0
EPSS
1%
Percentile
52.9
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
10.0 · CRITICAL
Vector
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
EPSS
0.00709 · 52.9th percentile
Weaknesses
CWE-22 · Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal'); CWE-306 · Missing Authentication for Critical Function
Published
2026-06-05T20:03Z
EPSS history
Timeline
  • 05 JUN 20:03Z
    Path Traversal in Altium Enterprise Server NIS Allows Unauthenticated Arbitrary File Write and File Read
    cvelistv5