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CriticalCISA KEVExploited in the wildPublic exploit

Insecure Deserialization in SAP NetWeaver Visual Composer Metadata Uploader

IdentifiersCVE-2025-42999CWE-502· Deserialization of Untrusted Data

CVE-2025-42999 is a critical insecure deserialization vulnerability in SAP NetWeaver Visual Composer Metadata Uploader, affecting the Visual Composer development server component. The issue arises when a privileged user can upload untrusted or malicious serialized content that is subsequently deserialized by the application without sufficient validation. Public reporting and the provided context describe the flaw as enabling execution of attacker-controlled payloads via crafted serialized objects, with SAP Security Note 3604119 addressing the issue. The vulnerability has been described as affecting VCFRAMEWORK 7.50 in at least some reporting, and it was also reported as part of exploit chains involving the related Visual Composer flaw CVE-2025-31324.

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation can compromise confidentiality, integrity, and availability of the affected host system. Reporting in the provided context states that attackers can achieve arbitrary command execution or arbitrary code execution, deploy malicious payloads or webshells, escalate privileges, and obtain unauthorized system control. In chained attacks with CVE-2025-31324, the flaw was reported to help bypass authentication and enable remote code execution with SAP administrator (<sid>adm) privileges, potentially resulting in full SAP application and underlying operating system compromise, data theft, operational disruption, and lateral movement.

Mitigation

If you can’t patch tonight, do this now.

If immediate patching is not possible, disable or restrict access to the deprecated Visual Composer component and specifically limit exposure of the Metadata Uploader and related developmentserver endpoints. Restrict network access to trusted administrative sources only, monitor for suspicious uploads and unexpected JSP/Java/class files in NetWeaver directories, forward logs to centralized monitoring, and use available Onapsis/Mandiant scanners and IoC tooling referenced in the provided context to assess exposure and detect compromise.

Remediation

Patch, then assume compromise.

Apply SAP Security Note 3604119, which directly addresses CVE-2025-42999 and is reported in the provided context to fix the underlying root cause associated with the related Visual Composer attack path. Organizations should update all affected SAP NetWeaver/Visual Composer components to the vendor-fixed version levels identified by SAP and verify that the patch has been successfully deployed across all relevant instances, including internet-exposed systems.
PUBLIC EXPLOITS

Exploits

No public exploits tracked yet. Mallory keeps watching.

VALID 0 / 0 TOTALView more in app

No public exploit code observed for this vulnerability.

EXPOSURE SURFACE

Affected products & vendors

Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.

VendorProductType
SAPNetweaverapplication

Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.

What this page doesn’t show

The version that knows your environment.

This page is what’s public. Mallory adds the parts that aren’t: which of your assets are affected, which adversaries are exploiting it right now, which detections to deploy, and what to do tonight.
Exposure mapping

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Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware12

Malware families riding this exploit, with evidence and IOCs.

Detection signatures1

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity31

Community discussion across Reddit, Mastodon, and other social sources.