CVE-2026-9129
Published: 20 May 2026
Summary
CVE-2026-9129 is a critical-severity Path Traversal (CWE-22) vulnerability in Altium Enterprise Server (inferred from references). Its CVSS base score is 9.4 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Data from Local System (T1005); ranked at the 14.9th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-31148
Vulnerability details
A path traversal vulnerability exists in the Altium Enterprise Server Viewer StorageController due to improper handling of file path route parameters. On on-premise deployments that use local filesystem storage, a regular authenticated user can supply a URL-encoded absolute path (such…
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as an encoded drive letter) in a Viewer storage API request, causing the configured storage root to be discarded and allowing arbitrary files to be read from the server filesystem. Because the readable files include the server's master configuration, which stores database credentials, signing key locations, certificate passwords, and OAuth secrets, exploitation can lead to disclosure of all server secrets and full compromise of the server and its data. Cloud deployments are not affected, as they use object storage and do not enable this component.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Path traversal enables direct arbitrary local file read (T1005), specifically exposing credential/secrets files (T1552.001).
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Automated marking applies security attributes to system outputs, making it harder for attackers to exploit unmarked sensitive information leading to unauthorized exposure.
Proper attribute retention and permitted-value enforcement limits unauthorized actors from accessing sensitive information lacking correct labels.
Prevents unauthorized exposure of sensitive information by prohibiting untrusted external systems from processing or storing it.
By enforcing authorization matching prior to sharing, the control reduces the risk of exposing sensitive information to unauthorized actors.
Review and removal of nonpublic information from publicly accessible systems directly prevents exposure of sensitive data to unauthorized actors.
Data mining protection mechanisms detect and block unauthorized bulk extraction of sensitive data, directly mitigating exposure to unauthorized actors.
Literacy training teaches users to recognize and avoid actions that result in unauthorized exposure of sensitive information.
Retaining and monitoring training records confirms personnel have completed privacy and security awareness training on handling sensitive data, reducing the chance of unauthorized exposure due to lack of knowledge.