CyberSecBulletin
CVE-2026-93758NVD status: Analyzed

Mongoid: Authorization Bypass Through User-Controlled Key

Published Updated By the CyberSecBulletin desk

CVE-2026-93758 is a high-severity authorization bypass through user-controlled key vulnerability in Mongoid from MongoDB, with a CVSS 3.1 base score of 8.1 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected Mongoid versions: 9.1.0; 9.0.0 through 9.0.11; 8.1.0 through 8.1.12, and others listed below. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.36% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of Mongoid you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on jira.mongodb.org for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
MongoDBMongoid9.1.0; 9.0.0 through 9.0.11; 8.1.0 through 8.1.12; 8.0.0 through 8.0.12Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
NoneAvailability is not affected.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N. Scored by CNA (mongodb.com).

Scoring systemScoreSeverityScored by
CVSS 4.08.6HighCNA (mongodb.com)
CVSS 3.18.1HighCNA (mongodb.com)

Official description

An insecure direct object reference in the nested attributes handling of the Mongoid object-document mapper may allow a user with basic application privileges to reference a record identifier that is not their own. Processing such a request can cause that record to be looked up without the usual ownership or scoping restrictions, then updated and linked to the requesting user's own record. This may result in unintended disclosure and unauthorized modification of data belonging to other users of the application.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Authorization Bypass Through User-Controlled Key

The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.

How developers prevent this class of flaw

  • For each and every data access, ensure that the user has sufficient privilege to access the record that is being requested.
  • Make sure that the key that is used in the lookup of a specific user's record is not controllable externally by the user or that any tampering can be detected.
  • Use encryption in order to make it more difficult to guess other legitimate values of the key or associate a digital signature with the key so that the server can verify that there has been no tampering.

More Authorization Bypass Through User-Controlled Key vulnerabilities (CWE-639)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Mongoid

All Mongoid vulnerabilities

Recent Authorization Bypass Through User-Controlled Key vulnerabilities

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