High severity · published Feb 10, 2026
CVE-2026-1849
Mongod can run out of stack memory when expressions create deeply nested documents
7.5
CVSS
0.3%
EPSS
No
On KEV
Description
MongoDB Server may experience an out-of-memory failure while evaluating expressions that produce deeply nested documents. The issue arises in recursive functions because the server does not periodically check the depth of the expression.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 25% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MO
MongoDB · MongoDB
7.0.0 before 7.0.29; 8.0.0 before 8.0.18; 8.2.0 before 8.2.2 · source: NVD
MS
MongoDB Server · MongoDB Inc
8.0 before 8.0.18; 7.0 before 7.0.29; 8.2 before 8.2.2 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-1849
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-1849
Vendor Advisory
https://jira.mongodb.org/browse/SERVER-102364
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