CVE-2026-1849: Mongod can run out of stack memory when expressions create deeply nested documents

Published Feb 10, 2026
·
Updated

MongoDB Server may experience an out-of-memory failure while evaluating expressions that produce deeply nested documents. The issue arises in recursive functions because the server does not periodically check the depth of the expression.

Affected Software

4 affected components
MongoDB MongoDB Server
MongoDB MongoDB>=7.0.0<7.0.29
MongoDB MongoDB>=8.0.0<8.0.18
MongoDB MongoDB>=8.2.0<8.2.2

Event History

Feb 10, 2026
CVE Published
via MITRE·06:52 PM
Data Sourced
via MITRE·06:52 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·07:15 PM
DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2026-1849?

CVE-2026-1849 is considered a critical vulnerability due to the potential for out-of-memory failures in MongoDB Server.

2

How does CVE-2026-1849 affect MongoDB Server?

CVE-2026-1849 causes MongoDB Server to run out of stack memory when expressions evaluate deeply nested documents.

3

What are the potential impacts of CVE-2026-1849?

The potential impacts of CVE-2026-1849 include server crashes and disrupted services due to out-of-memory errors.

4

How can I mitigate CVE-2026-1849?

Mitigation for CVE-2026-1849 involves using best practices to avoid deeply nested documents and monitoring server performance.

5

Which versions of MongoDB Server are affected by CVE-2026-1849?

CVE-2026-1849 affects all currently supported versions of MongoDB Server that do not implement patched solutions.

Contact

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