CVE intelligence and bounded remediation

CVE-2026-12686 — An authenticated user could manipulate a company ID parameter in a POST request to the backend to gain unauthorised access to other...

Critical CVSS 9.3

An authenticated user could manipulate a company ID parameter in a POST request to the backend to gain unauthorised access to other companies hosted within the same subdomain environment. The application does not adequately verify whether the requested company ID belongs to the authenticated user’s session, resulting in a cross-tenant authorisation bypass. If this vulnerability is successfully exploited, it allows unauthorised access to sensitive customer information, including billing data, and may enable the unauthorised modification of third-party data.

Severity
Critical
CVSS
9.3 (4.0)
Published
2026-07-06
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-639

Affected products

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Matched remediation archetype

Authorization bypass, IDOR, and cross-tenant access

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Check exposure

  • Map object and action authorization checks across API, UI, batch, import/export, and background-job paths.
  • Identify tenant, ownership, role, and policy boundaries for affected resources and administrative operations.
  • Use synthetic fixtures to compare intended access matrices without accessing another user's real data.

Remediate safely

  • Enforce server-side authorization at each resource access and state transition using the authenticated principal and trusted tenant context.
  • Scope data queries by tenant and ownership; treat client-supplied identifiers, roles, and policy claims as untrusted.
  • Add deny-by-default policy tests for horizontal and vertical access across every affected transport.

Authoritative sources

Complete CVE record and remediation plan

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