CVE-2026-40683

HIGH EPSS 23.4%

Published Apr 14, 20262mo ago · Modified Jun 17, 20262w ago

7.7 CVSS 3.1

High

Published Apr 14, 2026 2mo ago

Last Modified Jun 17, 2026 2w ago

Description

In OpenStack Keystone before 28.0.1, the LDAP identity backend does not convert the user enabled attribute to a boolean when the user_enabled_invert configuration option is False (the default). The _ldap_res_to_model method in the UserApi class only performed string-to-boolean conversion when user_enabled_invert was True. When False, the raw string value from LDAP (e.g., "FALSE") was used directly. Since non-empty strings are truthy in Python, users marked as disabled in LDAP were treated as enabled by Keystone, allowing them to authenticate and perform actions. All deployments using the LDAP identity backend without user_enabled_invert=True or user_enabled_emulation are affected.

CVSS Details

Base Score

7.7

Exploitability

1.8

Impact

5.3

Vector string

CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:H

Attack Vector Network

Attack Complexity High

Privileges Required Low

User Interaction None

Scope Changed

Confidentiality Low

Integrity Low

Availability High

Threat Intelligence

EPSS Exploit Probability

23.4% percentile

Exploit & Patch Status

No Known Exploit

No Patch Available

Weaknesses 1

CWE-843

References 4

bugs.launchpad.net https://bugs.launchpad.net/keystone/+bug/2121152
bugs.launchpad.net https://bugs.launchpad.net/keystone/+bug/2141713
review.opendev.org https://review.opendev.org/958205
openwall.com https://www.openwall.com/lists/oss-security/2026/04/14/9

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.