External risk intelligence

SAP NetWeaver AS ABAP Authentication Bypass Vulnerability.

CVE advisorySeverity: CRITICAL (CVSS 10.0)

CVE-2026-120017

SAP NetWeaver AS ABAP serves as a core application platform for enterprise environments. These systems are frequently deployed as public-facing web interfaces, portals, or API gateways to support business processes, making them reachable via the internet in common deployment patterns.

Halo Surface Signal: 4 out of 5 — likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

A critical vulnerability exists in SAP NetWeaver AS ABAP and ABAP Platform, allowing unauthenticated attackers to bypass authentication and impersonate users. This could lead to a complete system compromise with significant impact on data confidentiality, integrity, and availability, potentially affecting connected systems.

Authentication bypass allows impersonation of any user.
Critical systems could be fully compromised.
Confirm relevance and assess exposure of SAP platforms.

Attack Path

How an attacker could exploit the issue

An unauthenticated attacker can exploit this vulnerability by sending specially crafted data to SAP NetWeaver AS ABAP and ABAP Platform. This data can bypass the system's insufficient verification of incoming authentication assertions, allowing the attacker to impersonate any user, including those with administrative privileges. This could lead to a complete compromise of the affected system and potentially impact connected systems.

No authentication required for entry.
Specially crafted data triggers vulnerability.
Risk of full system compromise.

Live Threat

Current exploitation, exposure, and threat context

Under certain configurations, SAP NetWeaver AS ABAP and ABAP Platform may allow an unauthenticated attacker to bypass authentication by submitting specially crafted data. This could enable an attacker to impersonate arbitrary users, including those with privileged accounts, potentially leading to a full system compromise affecting confidentiality, integrity, and availability.

System credentials and data could be at risk.
Attackers could bypass authentication checks.
A full system compromise could occur.

Operational Fix

Recommended remediation, mitigation, and detection steps

SAP NetWeaver AS ABAP and ABAP Platform are core components likely managed by infrastructure or platform teams. Initial actions should focus on identifying all instances, determining their business criticality and external reachability, and then assigning ownership to the relevant application or system administrators for planned remediation.

Infrastructure/Platform teams should own the issue.
Verify instance reachability and business criticality.
Plan remediation based on confirmed risk.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

Halo Threat Intelligence helps prioritize remediation with Halo Surface Signal and H/A/L/O context. Start exposure validation with a free external attack surface trial.

Free EASM Trial See How Signal Works

Frequently asked questions

What is SAP NetWeaver AS ABAP?

SAP NetWeaver AS ABAP is a fundamental application server and development platform used to host critical enterprise business processes. It acts as the backbone for many SAP applications, often functioning as a portal or gateway that manages user interactions and data exchanges across complex business environments.

How does CVE-2026-120017 bypass authentication?

The vulnerability involves a flaw in how the system verifies incoming authentication assertions, classified as CWE-347 (Improper Verification of Cryptographic Signature). Because the platform fails to properly validate these identity tokens, an attacker can submit manipulated data that tricks the system into accepting them as a legitimate, authenticated user, including those with administrative rights.

Do I need special access to trigger this bug?

No. The vulnerability does not require any prior authentication or special credentials to trigger. An attacker only needs to send specially crafted data to the affected system. However, this only applies to specific system configurations where these authentication assertions are incorrectly processed; it is not triggered by standard, fully validated login attempts.

Why is this CVE considered high risk for internet-facing systems?

Halo Surface Signal notes that SAP NetWeaver AS ABAP is frequently deployed as a public-facing interface or API gateway to support external business needs. Because the vulnerability is exploitable over a network without requiring authentication, any instance reachable from the internet is significantly more accessible to attackers than a system protected by an internal network boundary.

What should I do if I run this software?

Your first step is to locate all instances of SAP NetWeaver AS ABAP within your environment and determine which are reachable from the internet. Once mapped, coordinate with your application and infrastructure teams to verify the specific configurations in use. Prioritize these systems based on their business criticality and ensure they are ready for the security updates provided by the vendor.

References

me.sap.com/notes/3849308

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.