Uncontrolled Resource Consumption in MongoDB Server Aggregation Framework via Internal Expression Leads to Denial of Service

published 2026-11-10 yesterday modified 2026-11-10 yesterday also EUVD-2026-122902

cvss: 6.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 24%
public exploits: 0; none known

An issue in MongoDB server’s aggregation framework allows an authenticated user with read privileges to cause a denial of service by sending specially crafted aggregate commands using an internal expression. Despite its internal naming, this expression is registered as accessible to any authenticated client. By supplying crafted input parameters across multiple concurrent connections, each evaluation triggers unbounded memory allocations with no per-expression memory limits enforced. This can exhaust available server memory and cause the mongod process to be terminated by the operating system’s out-of-memory killer.

Patch / fix

fixed in 1

MongoDB MongoDB Server 7.0.48, 8.0.37, 8.3.16, 9.0.7

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Exploit prediction

0.31% chance of exploitation in the next 30 days, higher than 24% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by	version	score	vector
CNA	4.0	7.1	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CNA	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CNA	4.0	7.1	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

MongoDB MongoDB Server

Classification

Weakness

CWE-770 Allocation of Resources Without Limits or Throttling

Technology feeds

MongoDB rss critical rss

References

jira.mongodb.org /browse/SERVER-132430

Sources

CVE List CVE-2026-120810
NVD CVE-2026-120810

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