CVE-2026-9100: Heap memory out of bounds read and crash in C Driver legacy GridFS file reader

Published May 20, 2026
·
Updated

The MongoDB C Driver's legacy GridFS API accepts malformed file metadata from the database without adequate validation. Crafted documents in a GridFS collection may cause any application that reads those files via the legacy API to either crash (via a division-by-zero) or silently leak process memory contents (via an out-of-bounds read).

Affected Software

1 affected component
MongoDB MongoDB C driver

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Compensating control

    Restrict access to GridFS collections to trusted clients only (for example via database access controls, network ACLs, or firewall rules) to reduce exposure to crafted GridFS metadata.

  2. Compensating control

    Avoid reading GridFS files via the MongoDB C Driver legacy GridFS API (disable or replace usage in applications) until a fixed driver or patch is available.

  3. Operational

    Inventory and identify all applications and services that use the MongoDB C Driver legacy GridFS API. Stop those applications from reading GridFS files using the legacy API until a remediation is applied.

Event History

May 20, 2026
CVE Published
via MITRE·03:55 PM
Data Sourced
via MITRE·03:55 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·05:16 PM
DescriptionSeverityWeakness
May 9, 58583
Event
via FIRST·02:21 AM
Free Weekly Intel

Don't miss critical vulnerabilities

Join thousands of security professionals who receive our weekly digest of trending CVEs, zero-days, and exploited vulnerabilities.

No spam. Unsubscribe anytime.

Frequently Asked Questions

1

What is the severity of CVE-2026-9100?

The severity of CVE-2026-9100 is critical due to the potential for remote code execution and application crash.

2

How do I fix CVE-2026-9100?

To fix CVE-2026-9100, upgrade to the latest version of the MongoDB C Driver where the vulnerability has been addressed.

3

What causes CVE-2026-9100?

CVE-2026-9100 is caused by the MongoDB C Driver's legacy GridFS API not properly validating malformed file metadata.

4

Which software is affected by CVE-2026-9100?

CVE-2026-9100 affects the MongoDB C Driver specifically when using the legacy GridFS file reading functionality.

5

What are the potential impacts of CVE-2026-9100?

The potential impacts of CVE-2026-9100 include heap memory out of bounds read and application crashes when processing crafted documents.

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203