CVE-2026-93761 PUBLISHED

Denial of service via unbounded regex matching in Mongoid's in-memory query matcher

Assigner: mongodb
Reserved: 18.09.2026 Published: 18.09.2026 Updated: 18.09.2026

An inefficient regular expression complexity issue in the in-memory query evaluation component of the Mongoid library may allow an unauthenticated party to cause excessive processing within an embedding application process. Applications that place user-supplied text into a pattern-matching query condition on an embedded association may become unresponsive.

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CVSS Score: 8.7

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

CVSS 4.0

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS Score: 7.5

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

CVSS 3.1

Product Status

Vendor	MongoDB Inc.
Product	Mongoid
Versions	Default: unaffected affected from 7.2.0 to 7.2.6 (incl.) affected from 7.3.0 to 7.3.5 (incl.) affected from 7.4.0 to 7.4.3 (incl.) affected from 7.5.0 to 7.5.4 (incl.) affected from 7.6.0 to 7.6.1 (incl.) affected from 8.0.0 to 8.0.12 (incl.) affected from 8.1.0 to 8.1.12 (incl.) affected from 9.0.0 to 9.0.11 (incl.) Version 9.1.0 is affected

References

https://jira.mongodb.org/browse/MONGOID-5981

Problem Types

CWE-1333: Inefficient Regular Expression Complexity CWE