CVE-2026-18688 PUBLISHED

Out-of-Bounds Read in MongoDB Aggregation Framework Leads to Denial of Service and Potential Memory Disclosure

Assigner: mongodb
Reserved: 03.08.2026 Published: 11.08.2026 Updated: 11.08.2026

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:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N
CVSS Score: 7.1

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	Low	Confidentiality	None
Attack Complexity	Low	Integrity	None	Integrity	None
Attack Requirements	None	Availability	High	Availability	None
Privileges Required	Low
User Interaction	None

CVSS 4.0

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H
CVSS Score: 7.1

Attack Vector	Network	Scope	Unchanged
Attack Complexity	Low	Confidentiality Impact	Low
Privileges Required	Low	Integrity Impact	None
User Interaction	None	Availability Impact	High

CVSS 3.1

Product Status

Vendor	MongoDB
Product	MongoDB Server
Versions	Default: unaffected affected from 8.3.0 to 8.3.8 (excl.) affected from 8.0 to 8.0.29 (excl.) affected from 7.0 to 7.0.40 (excl.)

References

https://jira.mongodb.org/browse/SERVER-129617

Problem Types

CWE-125: Out-of-bounds Read CWE