CVE-2026-27690
CriticalCVSS 9.1Exploitation Probability (EPSS)
Elevated risk50th percentile - higher than 50% of all known CVEs
Summary
An HTTP Request Smuggling vulnerability in SAP Approuter allows an unauthenticated attacker to send a crafted HTTP request, causing request-response desynchronization. This can expose user responses and make the system unavailable, with high impact on confidentiality and availability.
Risk Assessment
The risk for the organization includes leakage of sensitive user data and service disruption, affecting both confidentiality and availability.
Recommendation
Immediately update SAP Approuter to the latest patched version and deploy WAF rules to block suspicious HTTP requests.
Other vulnerabilities in SAP Approuter
See all- CVE-2026-66778Medium
SAP Approuter does not sufficiently sanitize certain request headers before forwarding traffic to internal components. An unauthenticated attacker could send a specially crafted request to obtain limited unauthorized access to information.
- CVE-2026-66777Medium
SAP Approuter does not sufficiently validate certain incoming requests before forwarding them to backend destinations. An attacker with low privileges could send specially crafted requests to bypass authorization checks and reach protected resources beyond their assigned scope.
- CVE-2026-66776Medium
SAP Approuter does not consistently enforce integrity verification on certain session-related request headers under specific conditions. An attacker with low privileges could send a specially crafted request that bypasses the integrity check and loads another user's session context.
- CVE-2026-66775Medium
SAP Approuter does not enforce cross-site request forgery protection on the authentication flow by default. An unauthenticated attacker could craft a malicious link and trick a victim into following it.
- CVE-2026-66774Low
SAP Approuter does not consistently handle certain error conditions. An attacker with low privileges could exploit this under a non-default configuration. Successful exploitation is highly complex, as it depends on conditions outside the attacker's control. This could result in a low impact on availability. There is no impact on confidentiality and integrity.
- CVE-2026-66761Medium
SAP Approuter does not enforce sufficient flow control in certain functionality. An attacker with low privileges could send high volumes of data without consuming responses, causing unbounded memory growth. This results in a low impact on availability, with no impact on confidentiality and integrity.
- CVE-2026-66760Medium
SAP Approuter does not correctly validate client certificates in certain callback flows. An attacker with low privileges, holding a certificate from the same trusted authority with matching subject values, could bypass the identity check. Successful exploitation could allow impersonation of a trusted internal component, resulting in a high impact on integrity and a low impact on confidentiality and availability.
- CVE-2026-58239Low
SAP Approuter does not sufficiently validate tenant context in inbound requests. An unauthenticated attacker could send specially crafted requests to spoof the tenant context under conditions not fully within their control. Successful exploitation could allow limited access to another tenant's information, resulting in a low impact on confidentiality. There is no impact on integrity and availability.
- CVE-2026-58238Medium
SAP Approuter does not sufficiently handle certain requests under specific conditions. An unauthenticated attacker could send specially crafted input that causes the component to crash and restart. Successful exploitation requires specific runtime conditions to be met, making the attack complex to execute. This results in a high impact on availability, with no impact on confidentiality and integrity.
- CVE-2026-58237Medium
WebSocket of SAP Approuter does not perform sufficient authorization checks in certain functionality. An attacker with low privileges could exploit this to access restricted functionality. Successful exploitation could allow the attacker to read sensitive information and perform limited modifications, resulting in a high impact on confidentiality and a low impact on integrity, with no impact on availability.
Original NVD description (English source)
Due to an HTTP Request Smuggling vulnerability in SAP Approuter, an unauthenticated attacker could send a specially crafted HTTP request that leads to request-response desynchronization. This could result in the exposure of user responses and cause the system to become unavailable. This leads to a high impact on confidentiality and availability.

