Medium severity · published Jun 9, 2026
CVE-2026-9743
Aggregation sub-pipeline null dereference may allow DoS via crafted getMore
6.5
CVSS
0.3%
EPSS
No
On KEV
Description
In MongoDB Server 8.0, an aggregation stage can leave its _subPipeline field null during processing of certain pipelines. If a getMore is subsequently issued on the same cursor, the server may dereference this null sub-pipeline when reattaching to the operation context, accessing an invalid address and crashing the process. This issue allows an authenticated user who can run aggregation pipelines to cause a denial of service by issuing a specially crafted aggregation followed by getMore on affected versions.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 23% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MO
MongoDB · MongoDB
8.0.0 before 8.0.24 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-9743
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-9743
Vendor Advisory
https://jira.mongodb.org/browse/SERVER-123688
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