Cyber Resilience

CVE-2026-9102

Critical

Published: 20 May 2026

Published
20 May 2026
Modified
21 May 2026
KEV Added
Patch
CVSS Score v4 9.4 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/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
EPSS Score 0.0056 42.6th percentile
Risk Priority 70 floored blend · peak EPSS

Summary

CVE-2026-9102 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 Exploit Public-Facing Application (T1190); ranked at the 42.6th 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

Vulnerability details

A path traversal vulnerability exists in the Altium Enterprise Server ComparisonService due to missing filename sanitization in the Gerber file upload APIs. A regular authenticated workspace user can supply a crafted filename in the multipart Content-Disposition header to escape the…

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intended temporary upload directory and write arbitrary files to any location on the server filesystem. Because content-controlled files can be written to web-accessible directories, this can be escalated to remote code execution in the context of the service account. It can also be used to overwrite application binaries or configuration files, leading to service takeover or denial of service.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1505.003 Web Shell Persistence
Adversaries may backdoor web servers with web shells to establish persistent access to systems.
Why these techniques?

Path traversal + unrestricted file upload in a public-facing server service directly enables exploitation of the application (T1190) to write and execute a web shell (T1505.003) for RCE; file overwrite also supports persistence but is secondary.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2026-22786Shared CWE-22, CWE-434
CVE-2024-13986Shared CWE-22, CWE-434
CVE-2025-2749Shared CWE-22, CWE-434
CVE-2012-10054Shared CWE-22, CWE-434
CVE-2025-35055Shared CWE-22, CWE-434
CVE-2022-50939Shared CWE-22, CWE-434
CVE-2025-22152Shared CWE-22, CWE-434
CVE-2019-25630Shared CWE-434
CVE-2025-12846Shared CWE-434
CVE-2026-1357Shared CWE-434

Affected Assets

Altium
Enterprise Server
inferred from references and description; NVD did not file a CPE for this CVE

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.

addresses: CWE-434

Requiring identifiable owners for portable devices reduces the attack surface for unrestricted uploads of dangerous file types via anonymous media.

addresses: CWE-434

Dangerous file uploads can be detonated in the chamber to determine malice before any production write or execution occurs.

addresses: CWE-434

Prevents unrestricted writing of arbitrary or malicious firmware by keeping hardware write-protect enabled except under tightly controlled manual procedures.

addresses: CWE-22

Validates pathnames and filenames to prevent traversal outside intended directories.

addresses: CWE-434

Scans files from external sources on download/open/execute, blocking unrestricted uploads of dangerous file types.

References