CVE-2026-17370 in API Connect
Summary
by MITRE • 11/07/2026
IBM API Connect 10.0.8.0 through 10.0.8.12 and 12.1.0.0 through 12.1.1.2 could allow a remote authenticated attacker to obtain an access token for another user due to improper authentication. The sign-in flow does not sufficiently verify the identity of the user completing it, which could allow another user's identity to be assumed.
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Analysis
by VulDB Data Team • 11/07/2026
The vulnerability identified in IBM API Connect versions 10.0.8.0 through 10.0.8.12 and 12.1.0.0 through 12.1.1.2 represents a critical failure in the authentication mechanism, specifically within the sign-in flow. This flaw allows remote authenticated attackers to obtain access tokens belonging to other users by exploiting insufficient verification of user identity during the login process. The core technical issue lies in the application's inability to properly bind session credentials or token issuance requests to the specific individual completing the action. When a user initiates a sign-in sequence, the system fails to rigorously validate that the entity providing authentication factors is indeed the intended account holder. This lack of strict identity verification creates an opening for attackers who have already gained authenticated access within the environment to manipulate session parameters or exploit state management flaws to hijack valid sessions or generate new tokens under different user identities.
From a technical perspective, this vulnerability aligns with CWE-287, which describes Improper Authentication, and more specifically relates to issues where authentication credentials are not properly validated against the intended subject. In many modern API gateways like IBM API Connect, the sign-in flow involves multiple steps including credential submission, token generation, and session establishment. If any of these steps do enforce strict checks on user context or if there is a flaw in how identity assertions are processed, an attacker can leverage this gap to assume another user's role. The attack typically requires prior authentication within the system, meaning it is not entirely unauthenticated but rather exploits the trust placed in existing sessions or login procedures. This type of vulnerability often stems from improper handling of session identifiers, lack of multi-factor verification for sensitive actions, or flaws in how identity providers communicate with the API gateway during token exchange processes.
The operational impact of this vulnerability is severe due to its potential for privilege escalation and data breach. By obtaining an access token for another user, an attacker can impersonate that individual within the IBM API Connect environment. This capability allows the adversary to perform actions as if they were the legitimate user, potentially accessing sensitive APIs, modifying configurations, or exfiltrating protected data depending on the permissions assigned to the targeted account. In enterprise environments where API Connect serves as a central hub for managing and securing microservices, such an identity assumption can lead to widespread compromise of downstream services that trust tokens issued by this gateway. The attacker gains the ability to bypass access controls designed to restrict functionality based on user roles, effectively neutralizing security boundaries established through role-based access control mechanisms.
This vulnerability maps directly to MITRE ATT&CK technique T1078, Valid Accounts, specifically within the context of account manipulation or session hijacking variants where an attacker leverages valid credentials but misuses them by assuming a different identity due to authentication flaws. It also touches upon aspects of T1621, Multi-Factor Authentication Request Interception, if the flaw involves bypassing secondary verification steps during sign-in. The persistence and lateral movement capabilities gained through this vulnerability are significant because access tokens often serve as long-lived credentials that can be used across multiple services integrated with IBM API Connect. Once an attacker secures a token for a high-privilege user, they may escalate their influence over the entire infrastructure managed by the platform.
Mitigation strategies must focus on strengthening identity verification processes and implementing robust session management practices. Organizations should immediately apply vendor-provided patches to update IBM API Connect to versions beyond 10.0.8.12 or 12.1.1.2, as these releases contain fixes for this authentication flaw. In the interim, if patching is not immediately feasible, administrators should enforce strict multi-factor authentication for all administrative and privileged accounts to reduce the risk of credential-based attacks succeeding even if identity verification fails. Additionally, implementing short-lived access tokens with frequent rotation can limit the window of opportunity for attackers to exploit stolen or forged tokens. Monitoring logs for anomalous sign-in patterns, such as rapid token requests from different user contexts using similar session data, can help detect exploitation attempts early. Regular security assessments and penetration testing focused on authentication flows are essential to identify and remediate similar weaknesses before they can be leveraged by adversaries.