SAP Patches Critical ICM2SHELL, ProxyGate Vulnerabilities

The first draft is short of the word range and one paragraph runs to four sentences. I'll restore source details and measure again.Enterprise software maker SAP on Tuesday announced the release of 42 new and updated security notes, including nine that resolve critical-severity vulnerabilities, as described in SecurityWeek's report.

Four of the new security notes address maximum-severity flaws in NetWeaver, in the Internet Communication Manager and the SAML2 Service Provider, and in Web Dispatcher and Gateway. Onapsis, the enterprise application security firm that analyzed the package, calls the ICM and Web Dispatcher defect ICM2SHELL and the Gateway defect ProxyGate.

This piece follows that November 2026 bulletin in the order the flaws were described, for administrators and security teams who patch NetWeaver, Web Dispatcher, Gateway, S4CRM, and BusinessObjects. It covers the four maximum-severity notes, the five other critical identifiers, and 17 high-severity fixes for memory corruption, denial of service, and information disclosure. It also covers new notes for the recently disclosed PHP2Shell and Node2Shell vulnerabilities in the Business AI Platform, which Onapsis includes in a monthly total of 43 new and updated notes.

01Four maximum-severity kernel security notes

The ICM and Web Dispatcher flaws, tracked as CVE-2026-76964 and CVE-2026-89126, are a single weakness in the SAP kernel component that receives HTTP, HTTPS, and WebSocket traffic. Onapsis calls that security defect ICM2SHELL. The two CVE identifiers name that one weakness in the kernel component shared by the Internet Communication Manager and Web Dispatcher.

The maximum-severity Gateway flaw in this set is CVE-2026-89103, which Onapsis refers to as ProxyGate. SAP also resolved a maximum-severity missing-authentication bug in NetWeaver, CVE-2026-120017. The four new maximum-severity notes are the ones for NetWeaver's Internet Communication Manager and SAML2 Service Provider, for Web Dispatcher, and for Gateway, and those four sit inside the nine critical-severity fixes from Tuesday.

02Crafted WebSocket messages past memory

According to Onapsis, ICM2SHELL is related to reassembling large WebSocket messages. Those messages may be split into fragments during a server-browser exchange and then put together by the receiver. The receiver that puts the fragments together is the ICM or Web Dispatcher, the kernel component that receives HTTP, HTTPS, and WebSocket traffic.

Onapsis explains what a malicious sequence does: "A specially crafted sequence of WebSocket messages makes the ICM or the WD write attacker-controlled data past the end of the memory it reserved for the connection." Depending on how that data is shaped, the result is either an immediate crash of the process or controlled corruption of its memory. In that description, WD is Web Dispatcher.

03Kernel exploit running as sid adm

ICM2SHELL, the enterprise application security firm says, could allow an attacker to execute operating system commands with <sid>adm privileges. Onapsis Research Labs provided SAP a working exploit that achieves full, unauthenticated remote code execution end to end, running arbitrary commands as <sid>adm on the target system. Onapsis says, "This is not a theoretical outcome."

The denial-of-service condition, in turn, reproduced on every SAP Kernel release tested. Onapsis reported that denial-of-service result for ICM2SHELL together with the working exploit it provided to SAP. Both the denial of service and the command execution sit in the kernel component that receives HTTP, HTTPS, and WebSocket traffic.

04ProxyGate and the prxyinfo list

Unauthenticated attackers could exploit the maximum-severity Gateway flaw, CVE-2026-89103, also called ProxyGate, to achieve remote code execution without user interaction. The bug is related to the prxyinfo access-control list, which should restrict requests to trusted networks only. If that list is left open, an attacker can send a series of requests that appear to be originating from an internal network, tricking the gateway into accepting them.

This allows an attacker to execute operating system commands with the <sid>adm privileges and gain full control over the SAP system. The attacker supplies no username, password, or certificate, and the gateway has already accepted the requests because they appear to come from an internal network.

Onapsis explains the scope of CVE-2026-89103 this way: "Because the flaw is in the SAP kernel, it affects a broad range of releases, including kernel versions that are already out of maintenance." The gateway runs not only on ABAP but also on AS Java, dual-stack, and standalone-gateway systems.

05User impersonation and other fixes

The maximum-severity missing-authentication bug in NetWeaver is CVE-2026-120017. In certain configurations, it could allow unauthenticated attackers to submit specially crafted data and impersonate arbitrary users, which could lead to full system compromise. That note stands apart from the five remaining critical notes in the same November 2026 bulletin, which carry different CVE identifiers.

The remaining five critical notes address vulnerabilities in NetWeaver under CVE-2026-109803 and CVE-2026-76965, in S4CRM under CVE-2026-109795, in Web Dispatcher under CVE-2026-89119, and in BusinessObjects under CVE-2026-109798. SAP also published 17 high-severity fixes, including multiple memory corruption, denial-of-service, and information disclosure bugs. Since the scheduled October 2026 security patches, SAP released new notes dealing with the recently disclosed PHP2Shell and Node2Shell vulnerabilities in its Business AI Platform and updated several other notes and advisories.

Onapsis, in its analysis of the patches, says this brings the total to 43 new and updated notes released this month. Tuesday's announcement was the release of 42 new and updated security notes, nine of them critical. The monthly total of 43 includes the PHP2Shell and Node2Shell notes for the Business AI Platform and the other advisories updated since the October 2026 patches.