CVE-2026-82040 in UTMStack
Summary
by MITRE • 10/02/2026
UTMStack before 11.2.16 contains a server-side request forgery vulnerability in IdentityProviderService.validateMetadataUrl() that allows authenticated attackers to make the server send requests to arbitrary internal or cloud metadata hosts by supplying a malicious metadata URL to the identity-providers endpoint. Attackers can exploit the POST/PUT /api/identity-providers endpoint with no validation of target host, IP, or scheme to perform internal network port scanning and access cloud instance-metadata services.
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Analysis
by VulDB Data Team • 10/02/2026
The vulnerability identified in UTMStack versions prior to 11.2.16 represents a critical server-side request forgery flaw located within the IdentityProviderService.validateMetadataUrl() function. This component is responsible for validating metadata URLs provided during the configuration of identity providers, which are essential components for managing authentication and authorization protocols such as SAML or OIDC in enterprise security architectures. The core technical deficiency lies in the absence of rigorous input validation regarding the target host, IP address, and URL scheme when processing requests directed at the POST/PUT /api/identity-providers endpoint. By failing to restrict the destination addresses to a predefined whitelist of trusted domains or internal network segments, the application inadvertently allows authenticated attackers to inject arbitrary URLs that direct the server to initiate HTTP connections on their behalf. This lack of validation enables an attacker to manipulate the backend service into making requests to destinations chosen entirely by the user input rather than legitimate identity provider endpoints.
The operational impact of this vulnerability is severe due to its potential for internal network reconnaissance and unauthorized access to cloud infrastructure metadata services. Because the server executes these requests with its own privileges, attackers can leverage the application as a proxy to scan internal networks that are not directly accessible from the external internet or untrusted zones. This capability effectively bypasses traditional perimeter defenses such as firewalls and intrusion detection systems that rely on source IP filtering, since the traffic appears to originate from the trusted UTMStack server itself. Furthermore, in cloud environments where UTMStack may be deployed, attackers can target instance metadata services typically found at addresses like 169.254.169.254 or similar internal endpoints. Accessing these services allows adversaries to retrieve sensitive configuration data, temporary security credentials, and other privileged information that facilitates further lateral movement within the compromised environment.
From a classification perspective, this vulnerability aligns with CWE-918 Server-Side Request Forgery (SSRF), specifically highlighting the failure to perform proper validation of user-supplied URLs before processing them server-side. The exploitation technique maps directly to ATT&CK Tactic TA0043 Reconnaissance and ATT&CK Technique T1561 Lost Access, as well as T1046 Network Service Discovery, because it enables attackers to discover live hosts and services within the internal network topology. Additionally, if cloud metadata is accessed, it relates to credential access techniques such as T1528 Steal Application Access Tokens or T1552 Unsecured Credentials, depending on the specific data retrieved from the metadata service. The vulnerability underscores a common misconfiguration pattern where administrative interfaces lack sufficient restrictions on outbound network connections initiated by backend services.
Mitigation strategies must focus on implementing strict allow-listing mechanisms for all outgoing requests originating from the IdentityProviderService component. Administrators should configure the application to only permit connections to explicitly defined, trusted identity provider domains and block any attempts to resolve or connect to private IP ranges, loopback addresses, or cloud metadata endpoints. Network-level controls such as egress filtering on the host running UTMStack can provide an additional layer of defense by blocking outbound traffic to non-essential ports and internal subnets. Upgrading to version 11.2.16 or later is essential as it resolves this validation gap. In environments where immediate patching is not feasible, deploying a web application firewall with SSRF detection capabilities may help mitigate exploitation attempts by inspecting the destination addresses of outbound requests initiated by the application.