MongoDB Server up to 7.0.34/8.0.23/8.2.9/8.3.2 Aggregation exchange assertion

Summaryinfo

A vulnerability classified as problematic has been found in MongoDB Server up to 7.0.34/8.0.23/8.2.9/8.3.2. This affects an unknown function of the component Aggregation Handler. The manipulation of the argument exchange leads to assertion. This vulnerability is listed as CVE-2026-9749. The attack may be initiated remotely. There is no available exploit. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in MongoDB Server up to 7.0.34/8.0.23/8.2.9/8.3.2 and classified as problematic. This issue affects some unknown processing of the component Aggregation Handler. The manipulation of the argument exchange with an unknown input leads to a assertion vulnerability. Using CWE to declare the problem leads to CWE-617. The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary. Impacted is availability. The summary by CVE is:

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.

It is possible to read the advisory at jira.mongodb.org. The identification of this vulnerability is CVE-2026-9749 since 05/27/2026. The exploitation is known to be easy. The attack may be initiated remotely. Technical details of the vulnerability are known, but there is no available exploit.

Upgrading to version 7.0.35, 8.0.24, 8.2.10 or 8.3.3 eliminates this vulnerability.

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Productinfo

Type

• Database Software

Vendor

• MongoDB

Name

• Server

Version

• 7.0.0
• 7.0.1
• 7.0.2
• 7.0.3
• 7.0.4
• 7.0.5
• 7.0.6
• 7.0.7
• 7.0.8
• 7.0.9
• 7.0.10
• 7.0.11
• 7.0.12
• 7.0.13
• 7.0.14
• 7.0.15
• 7.0.16
• 7.0.17
• 7.0.18
• 7.0.19
• 7.0.20
• 7.0.21
• 7.0.22
• 7.0.23
• 7.0.24
• 7.0.25
• 7.0.26
• 7.0.27
• 7.0.28
• 7.0.29
• 7.0.30
• 7.0.31
• 7.0.32
• 7.0.33
• 7.0.34
• 8.0.0
• 8.0.1
• 8.0.2
• 8.0.3
• 8.0.4
• 8.0.5
• 8.0.6
• 8.0.7
• 8.0.8
• 8.0.9
• 8.0.10
• 8.0.11
• 8.0.12
• 8.0.13
• 8.0.14
• 8.0.15
• 8.0.16
• 8.0.17
• 8.0.18
• 8.0.19
• 8.0.20
• 8.0.21
• 8.0.22
• 8.0.23
• 8.2.0
• 8.2.1
• 8.2.2
• 8.2.3
• 8.2.4
• 8.2.5
• 8.2.6
• 8.2.7
• 8.2.8
• 8.2.9
• 8.3.0
• 8.3.1
• 8.3.2

License

• open-source

CPE 2.3info

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CPE 2.2info

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Entryinfo

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