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	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:mongodb:mongodb:::::-:::*
	cpe:2.3:a:mongodb:mongodb:::::-:::*
	cpe:2.3:a:mongodb:mongodb:::::-:::*
	cpe:2.3:a:mongodb:mongodb:::::-:::*

History

No history.

Information

Published : 2026-06-09 23:17

Updated : 2026-07-23 09:10

NVD link : CVE-2026-9749

Mitre link : CVE-2026-9749

CVE.ORG link : CVE-2026-9749

JSON object : View

Products Affected

mongodb

mongodb

CWE

CWE-617

Reachable Assertion

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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."}, {"lang": "es", "value": "Este problema puede ocurrir al ejecutar una pipeline de agregaci\u00f3n que utiliza la etapa interna $exchange configurada con particionamiento por rango de claves y entrega que preserva el orden. Si un \u00fanico rango de claves produce suficientes documentos para llenar su b\u00fafer de intercambio (es decir, muchos resultados se enrutan al mismo consumidor), el servidor alcanza la ruta de c\u00f3digo donde se detecta un b\u00fafer completo por consumidor, pero la 'marca de agua alta' interna para ese rango de claves no se actualiza seg\u00fan lo previsto."}], "lastModified": "2026-07-23T09:10:00.113", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:mongodb:mongodb:*:*:*:*:-:*:*:*", "vulnerable": true, "matchCriteriaId": "5E18B14E-2313-48F8-B01A-EE5B6FCB2454", "versionEndExcluding": "7.0.35", "versionStartIncluding": "7.0.0"}, {"criteria": "cpe:2.3:a:mongodb:mongodb:*:*:*:*:-:*:*:*", "vulnerable": true, "matchCriteriaId": "6E432AA0-551E-40F1-B3D9-F0855A0EA3BF", "versionEndExcluding": "8.0.24", "versionStartIncluding": "8.0.0"}, {"criteria": "cpe:2.3:a:mongodb:mongodb:*:*:*:*:-:*:*:*", "vulnerable": true, "matchCriteriaId": "BF13D90A-C5F8-4199-B914-0E67E160BFAB", "versionEndExcluding": "8.2.10", "versionStartIncluding": "8.2.0"}, {"criteria": "cpe:2.3:a:mongodb:mongodb:*:*:*:*:-:*:*:*", "vulnerable": true, "matchCriteriaId": "56EC12EE-0326-44DA-8BEA-EBCD528FE886", "versionEndExcluding": "8.3.3", "versionStartIncluding": "8.3.0"}], "operator": "OR"}]}], "sourceIdentifier": "cna@mongodb.com"}