CVE-2026-9749

This issue can occur when running an aggregation pipeline that uses the internal $exchange stage configured with key-range partitioning and order-preserving delivery. If a single key range produces enough documents to fill its exchange buffer (that is, many results are routed to the same consumer), the server reaches the code path where a full per-consumer buffer is detected but the internal "high watermark" for that key range is not updated as intended.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://jira.mongodb.org/browse/SERVER-124031

Configurations

No configuration.

History

09 Jun 2026, 23:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-09 23:17

Updated : 2026-06-09 23:17

NVD link : CVE-2026-9749

Mitre link : CVE-2026-9749

CVE.ORG link : CVE-2026-9749

JSON object : View

Products Affected

No product.

CWE

CWE-617

Reachable Assertion

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