CVE-2026-44745 in Approuter
Summary
by MITRE • 07/14/2026
SAP Approuter does not properly validate incoming request headers during the OAuth2 login flow under certain configurations. This allows an unauthenticated remote attacker to craft a malicious link which, when clicked by a victim, could lead to unauthorized access. Successful exploitation results in a high impact to the confidentiality and integrity with no impact on the availability of the application.
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Analysis
by VulDB Data Team • 07/14/2026
The vulnerability in SAP Approuter represents a critical authorization bypass flaw that stems from inadequate input validation during the OAuth2 authentication process. This weakness specifically manifests when the application router fails to properly sanitize and validate incoming HTTP headers that are part of the OAuth2 login flow. The flaw exists in the way the system processes authentication tokens and header information, creating a pathway for malicious actors to manipulate the authentication sequence without proper credentials.
The technical implementation of this vulnerability allows attackers to construct specially crafted URLs or links that exploit the insufficient header validation mechanisms within the SAP Approuter component. When a victim clicks on such a malicious link, the system's inadequate security checks permit the unauthorized request to proceed through the authentication flow, effectively bypassing normal access controls. This occurs because the application router does not perform adequate verification of the headers containing authentication context, allowing attackers to inject forged or manipulated header values that appear legitimate to the system.
From an operational perspective, this vulnerability creates a significant risk to the confidentiality and integrity of systems protected by SAP Approuter, as it enables unauthorized access to sensitive applications and data without proper authentication. The impact is particularly severe because the attack requires no prior credentials or privileged access from the attacker, making it highly exploitable in scenarios where users might be tricked into clicking malicious links through social engineering tactics. The availability of the application remains unaffected, but the compromise of confidentiality and integrity represents a serious breach of security controls that can lead to data theft, unauthorized modifications, and potential lateral movement within the attacked environment.
The vulnerability aligns with CWE-285 which addresses improper authorization in authentication flows, and demonstrates characteristics consistent with ATT&CK technique T1566 related to phishing attacks. Organizations should implement immediate mitigations including updating to patched versions of SAP Approuter, implementing additional header validation controls, and deploying network monitoring solutions to detect suspicious authentication patterns. Security teams should also conduct thorough assessments of their OAuth2 implementations and consider implementing additional layers of authentication verification, such as multi-factor authentication, to reduce the overall risk exposure from this class of vulnerability.