CVE-2026-9749
Using MaxKey() may crash the server
CVSS Score
6.5
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-617 |
| Vendor | mongodb |
| Product | mongodb server |
| Ecosystems | |
| Industries | Technology |
| Published | Jun 9, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Affected Versions
MongoDB / MongoDB Server
8.3.0 < 8.3.3 8.2.0 < 8.2.10 8.0.0 < 8.0.24 7.0.0 < 7.0.35