Cyber Resilience

CVE-2026-9152

Critical

Published: 21 May 2026

Published
21 May 2026
Modified
21 May 2026
KEV Added
Patch
CVSS Score v4 10.0 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/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 0.0034 25.8th percentile
Risk Priority 70 floored blend · peak EPSS

Summary

CVE-2026-9152 is a critical-severity Missing Authentication for Critical Function (CWE-306) vulnerability in Altium Enterprise Server (inferred from references). Its CVSS base score is 10.0 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 25.8th 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 missing authentication vulnerability exists in the Altium 365 SearchService. A legacy SOAP endpoint exposes search index operations without requiring authentication, session tokens, or any form of identity verification. An unauthenticated network attacker who can reference a target workspace's identifier…

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can interact with that workspace's search index, crossing tenant boundaries. Successful exploitation allows reading a workspace's indexed contents (such as component data, project and folder names, and user metadata) and injecting, modifying, or deleting search index entries. These operations affect the search index only, not the underlying vault data, but they can disclose sensitive workspace information and compromise the integrity and availability of search results. Altium 365 cloud deployments are affected; on-premise Altium Enterprise Server is not affected.

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.
Why these techniques?

Missing authentication on a public-facing legacy SOAP endpoint directly enables remote exploitation to access and manipulate tenant search indexes.

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

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-306

Requires established identification and authentication to unlock, mitigating missing authentication for continued system access.

addresses: CWE-306

Requiring identification and rationale for actions allowed without authentication ensures critical functions are not left unprotected by forcing review of authentication requirements.

addresses: CWE-306

Authorizing mobile device connections to organizational systems ensures authentication is performed for this critical access function.

addresses: CWE-639

Per-request decision making makes it harder to bypass authorization using user-controlled keys without proper validation in the decision process.

addresses: CWE-306

Guarantees critical functions are protected by mandatory invocation of the access control mechanism.

addresses: CWE-639

Consistent enforcement of approved authorizations makes bypassing via user-controlled keys ineffective.

addresses: CWE-306

Auditing sessions makes it possible to detect access to critical functions without required authentication.

addresses: CWE-306

The assessment process confirms authentication is present and effective for critical functions, preventing exploitation from missing authentication.

References