Uncontrolled Resource Consumption in MongoDB Server Per-Namespace Encrypted-Field Statistics Table Leads to Denial of Service

published 2026-11-10 yesterday modified 2026-11-10 yesterday also EUVD-2026-122835

cvss: 4.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 29%
public exploits: 0; none known

MongoDB Server maintains an in-memory table of per-namespace statistics for operations that carry encrypted-field information. Entries are created for any namespace supplied in a request, with no limit on the number of entries and no way to remove entries that never corresponded to a real collection. A user with basic read privileges who repeatedly issues ordinary read commands referencing arbitrary namespace names may cause the server process to retain steadily increasing amounts of memory and to slow down on the affected code path; the memory is reclaimed only by restarting the process.

Patch / fix

fixed in 1

MongoDB MongoDB Server 8.0.37, 8.3.16, 9.0.7

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Exploit prediction

0.36% chance of exploitation in the next 30 days, higher than 29% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by	version	score	vector
CNA	4.0	5.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
CNA	3.1	4.3	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
CNA	4.0	5.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/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-135737

Sources

CVE List CVE-2026-120820
NVD CVE-2026-120820

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