Deserialization of Untrusted DataWeakness · CWE-502

CVE-2025-42928

CRITICAL · 9.1 CVSS v3.1 Published 2025-12-09
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
97/100
Remediation priority · Urgent
Remotely reachable Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Under certain conditions, a high privileged user could exploit a deserialization vulnerability in SAP jConnect to launch remote code execution. The system may be vulnerable when specially crafted input is used to exploit the vulnerability resulting in high impact on confidentiality, integrity and availability of the system.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

SAP jConnect contains a deserialization vulnerability that allows a high-privileged authenticated user to execute arbitrary code by providing specially crafted input. The flaw affects the deserialization of untrusted data, enabling remote code execution with the privileges of the affected service.

MitigationApply the relevant SAP security patch for jConnect and review deserialization configurations to ensure only trusted data sources are processed. Consider network segmentation to limit high-privileged access.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify SAP jConnect installation
    Locate the jConnect jar files in the application server's lib directory, typically under SAP NetWeaver or SAP Java AS installations. Common paths include $SAP_HOME$/j2ee/cluster/ etc. Check for jconn4.jar or similar jConnect driver files.
    Affected if SAP jConnect driver is present on the system
  2. Determine jConnect version
    Inspect the manifest file within the jConnect jar or run: jar -xf jconn4.jar META-INF/MANIFEST.MF && cat META-INF/MANIFEST.MF. Also check file properties of the jconn4.jar file.
    Affected if Installed version cannot be confirmed as patched or falls outside known secure version ranges
  3. Verify deserialization configuration
    Review application configuration files (like ser-config.xml, deployment descriptors) and Java deserialization settings in the SAP J2EE/Java AS admin console. Check if custom deserializers or object inputs are configured to accept untrusted data.
    Affected if Deserialization of untrusted data is permitted without strict whitelisting or validation
  4. Audit high-privileged user access
    Review SAP user management and role assignments. Check which users have high-privileged roles (like SAP_ADMIN, J2EE_ADMIN) that could leverage this vulnerability. Query table USR02 and check roles via transaction SUIM.
    Affected if Multiple high-privileged authenticated users exist or high-privileged access is not restricted to specific IPs/admin stations
  5. Inspect network exposure
    Check if the SAP Java instance ports (typically 5xx00 range for HTTP, 5xx01 for HTTPS) are exposed beyond the internal network. Review SAP Logon Pad connections and firewall rules.
    Affected if SAP Java services are reachable from untrusted networks or DMZ segments

The environment is affected if SAP jConnect is installed with a version that has not been patched, deserialization of untrusted data is enabled, and high-privileged authenticated users can access the vulnerable service.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply the relevant SAP security patch for jConnect and review deserialization configurations to ensure only trusted data sources are processed. Consider network segmentation to limit high-privileged access.

Have this fixed Scoped from the published advisory
  • Consultation4.0 h
  • Implementation6.0 h
  • Testing4.0 h
  • Review / QA2.0 h
16.0 hours of engineering $2,840
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Scan for this in your stack

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dbcve dependency scanner

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-42928 in production — separate from our analysis above.

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What this is

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What belongs here
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  • Version or environment caveats, and links to real fixes
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