High severity · published Aug 11, 2026
CVE-2026-18688
Out-of-Bounds Read in MongoDB Aggregation Framework Leads to Denial of Service and Potential Memory Disclosure
7.1
CVSS
0.4%
EPSS
No
On KEV
Description
An issue in MongoDB Server's aggregation framework could allow an authenticated user to trigger an out-of-bounds memory read by providing a specially formed numeric parameter in a certain aggregation pipeline stage. This could result in a server crash (denial of service) and may potentially expose a limited amount of memory contents.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 34% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MO
MongoDB · MongoDB
8.3.0 before 8.3.8; 8.0 before 8.0.29; 7.0 before 7.0.40 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-18688
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-18688
Vendor Advisory
https://jira.mongodb.org/browse/SERVER-129617
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