CVE-2026-115370
Description
A flaw was found in Incus. An authenticated user with instance creation privileges in a restricted project can bypass security restrictions by submitting a clustered refresh migration request for an existing instance. This allows the attacker to force the server to establish outbound TLS (Transport Layer Security) WebSocket connections, enabling them to probe network services reachable by the server.
Statement
This vulnerability has been rated as Moderate because successful exploitation requires pre-existing authenticated credentials with instance creation permissions, and the impact is confined to network reconnaissance without unauthorized data modification. Furthermore, Incus is not packaged or distributed within supported Red Hat Enterprise Linux environments or core container offerings. In environments where Incus is deployed independently, the risk remains restricted because attackers cannot execute code or directly alter cluster state through this mechanism.
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Application Data
Integrity
Technical Impact: Execute Unauthorized Code or Commands
Access Control
Technical Impact: Bypass Protection Mechanism
By providing URLs to unexpected hosts or ports, attackers can make it appear that the server is sending the request, possibly bypassing access controls such as firewalls that prevent the attackers from accessing the URLs directly. The server can be used as a proxy to conduct port scanning of hosts in internal networks, use other URLs such as that can access documents on the system (using file://), or use other protocols such as gopher:// or tftp://, which may provide greater control over the contents of requests.
Frequently Asked Questions
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