Path Traversal in Altium Projects Service Allows Arbitrary File Read

published 2026-06-05 5 mo ago modified 2026-07-23 3 mo ago also EUVD-2026-34919

cvss: 8.3; version 4.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.5%; EPSS 0.5% chance of exploitation in 30 days, percentile 44%
public exploits: 0; none known

A path traversal vulnerability exists in the Projects Service download endpoint shared by Altium Enterprise Server and Altium 365. An authenticated user can supply a crafted path parameter that bypasses validation, allowing arbitrary files (including entire directories returned as archives) to be read from the server filesystem.

Because the readable files include service configuration and credential material, exploitation can be used to gather information enabling further compromise. The issue can be combined with CVE-2026-11424 to reach the cloud-side endpoint. On multi-tenant Altium 365 deployments, the readable configuration could have exposed credentials shared across services. Altium Enterprise Server is fixed in 8.1.1; the issue has been remediated in Altium 365 at the service level.

Patch / fix

fixed in 1

Altium Altium Enterprise Server 8.1.1

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: 5 mo ago (2026-06-08)

Exploit prediction

0.52% chance of exploitation in the next 30 days, higher than 44% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	4.0	8.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N
CNA	4.0	8.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N/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

Affected products

Altium Altium Enterprise Server
Altium Altium 365

Classification

Weakness

CWE-22 Improper Limitation of a Pathname to a Restricted Directory
CWE-200 Exposure of Sensitive Information to an Unauthorized Actor

References

altium.com /platform/security-compliance/security-advisories

Sources

CVE List CVE-2026-11431
NVD CVE-2026-11431

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary