CVE-2026-17312 in API Connect
Summary
by MITRE • 11/07/2026
IBM API Connect 12.1.0.0 through 12.1.1.2 could allow a remote attacker to force a user to authenticate into an attacker-controlled account due to cross-site request forgery. The sign-in flow does not sufficiently verify that a login response belongs to the user's own request, which could link the victim's session to an account controlled by the attacker.
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Analysis
by VulDB Data Team • 11/07/2026
The vulnerability identified in IBM API Connect versions 12.1.0.0 through 12.1.1.2 represents a critical authentication bypass mechanism rooted in cross-site request forgery principles, specifically targeting the integrity of the sign-in flow. This flaw allows an unauthenticated remote attacker to manipulate the state of a victim's session by exploiting the lack of sufficient verification mechanisms during the authentication process. The core technical deficiency lies in the application's failure to validate that the login response returned from the identity provider or internal authentication service corresponds directly to the specific request initiated by the legitimate user. In standard secure implementations, unique tokens such as state parameters, nonces, or strict origin validation are employed to ensure that each authentication transaction is bound to its initiator and cannot be replayed or forged by a third party. Without these safeguards, an attacker can craft malicious requests that trigger the application's login endpoint with credentials controlled by the attacker, effectively hijacking the victim's active session context.
From a technical perspective, this vulnerability aligns closely with CWE-352, which describes Cross-Site Request Forgery (CSRF), although it manifests in a manner more akin to an authentication flow manipulation or state machine confusion rather than traditional CSRF attacks that modify account settings. The absence of robust request-response binding means that when the victim interacts with the application, potentially through a malicious link or automated script, the system accepts the login response associated with the attacker's credentials as valid for the current session. This results in the victim being authenticated under an identity controlled by the adversary without their knowledge or consent. The operational impact of this flaw is severe, as it compromises the fundamental principle of authentication integrity. An attacker who gains control over a user account can perform actions on behalf of that user within the API Connect environment, potentially accessing sensitive data, modifying configurations, or leveraging the compromised identity to attack downstream systems connected via the API gateway.
This vulnerability maps directly to MITRE ATT&CK technique T1078, specifically Valid Accounts, as it enables an attacker to establish a foothold using legitimate credentials that have been hijacked through session manipulation rather than stolen secrets. It also relates to T1621, Multi-Factor Authentication Interception, if the sign-in flow involves multi-factor steps where the initial authentication state is not properly isolated per request. The exploitation of this flaw does not require complex reverse engineering or binary analysis; it relies on social engineering or automated web-based attacks to trick a user into initiating a login sequence that the attacker has pre-configured with their own account details. This makes detection difficult for standard intrusion prevention systems, as the traffic appears to be legitimate authentication attempts from valid IP addresses and users.
Mitigation strategies must focus on implementing strict state validation within the authentication workflow. Developers should ensure that every sign-in request includes a unique, cryptographically secure random token, such as an OAuth 2.0 state parameter or OpenID Connect nonce, which is validated against the session context upon receiving the response from the identity provider. Additionally, enforcing SameSite cookie attributes for session cookies can prevent browsers from sending them in cross-site requests, thereby mitigating many forms of request forgery. Implementing origin and referer header validation provides an additional layer of defense by ensuring that authentication responses are only accepted if they originate from expected domains. Upgrading to a patched version of IBM API Connect is the primary remediation path, as these versions contain fixes for this specific logic error in the sign-in flow verification process. Organizations should also monitor for anomalous login patterns where session tokens appear to be associated with unexpected user identities or source IPs, which may indicate active exploitation attempts.