Memory Leak Vulnerability in MongoDB Server (CVE-2025-14847)

Historical catalog analysis: CISA added this entry on December 29, 2025. The entry reflects catalog information retrieved on August 31, 2026, not a snapshot archived on the inclusion date. Check current vendor guidance before acting.

What the vulnerability is

CVE-2025-14847 is an improper handling of length parameter inconsistency vulnerability (CWE-130) found in MongoDB and MongoDB Server. The flaw exists within the Zlib compressed protocol headers. If exploited, this vulnerability could allow an unauthenticated client to read uninitialized heap memory from the server.

Exposure and applicability

This vulnerability is particularly relevant for healthcare organizations, health plans, and business associates that utilize MongoDB to store large datasets, including electronic Protected Health Information (ePHI). Because the flaw allows an unauthenticated actor to potentially access memory, it presents a direct risk to the confidentiality requirements of the HIPAA Security Rule.

Organizations should determine if their environment employs MongoDB or any third-party products and open-source components that integrate this database server. The vulnerability’s presence in a protocol header means that exposure depends on how the server handles compressed network traffic.

Remediation priorities

Based on our analysis, healthcare security leaders and database administrators should prioritize the following actions to reduce risk:

1. Inventory and Version Audit: Identify all instances of MongoDB Server across clinical and administrative networks. This is a prerequisite for applying any vendor-supplied fixes.
2. Apply Vendor Mitigations: Following the guidance provided by MongoDB, apply the necessary patches or configuration changes to address the length parameter inconsistency in Zlib headers.
3. Network Access Control: As this vulnerability can be triggered by an unauthenticated client, restricting database access to known, authorized application servers via firewalls or VPC security groups could reduce the likelihood of external exploitation while patching is underway.

How to validate remediation

To verify that exposure has been reduced, administrators should:
* Confirm Versioning: Verify that the installed version of MongoDB matches the patched version specified in the vendor’s official security advisory.
* Configuration Review: Ensure that any required mitigation settings recommended by the vendor are active and consistently applied across all clusters.

Note that a version check alone does not guarantee total security, as it does not account for potential misconfigurations or other vulnerabilities.

Limits and open questions

It remains unknown whether this vulnerability has been utilized in active ransomware campaigns. Additionally, because the flaw may affect various proprietary implementations or third-party libraries using these protocol headers, organizations relying on embedded MongoDB instances should consult their specific software vendors for confirmation of a fix.

Applying mitigations could reduce the likelihood of unauthorized memory access, but it does not eliminate all risks associated with heap memory vulnerabilities. Residual risk remains if other unpatched vectors exist within the environment.

Source and editorial note

CVE-2025-14847: MongoDB and MongoDB Server Improper Handling of Length Parameter Inconsistency Vulnerability · Source date: December 29, 2025 · Retrieved August 31, 2026.

Material facts are tied to the cited primary source. Recommendations are independent defensive analysis unless attributed to the source. Confirm consequential decisions against current authoritative guidance.

Archive date: January 01, 2026. The displayed post date is assigned three days after the source date to organize this retrospective archive; it does not mean this site published the analysis then. First published by this site: September 22, 2026 at 01:29 UTC.

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