OpenStack Keystone up to 25.0.0/26.1.0/27.0.0/28.0.0 Configuration Options _ldap_res_to_model type confusion

CVSS Meta Temp Score
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CTI Interest Score
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6.2$0-$5k0.00

Summaryinfo

A vulnerability labeled as problematic has been found in OpenStack Keystone up to 25.0.0/26.1.0/27.0.0/28.0.0. The impacted element is the function _ldap_res_to_model of the component Configuration Options Handler. Such manipulation leads to type confusion. This vulnerability is traded as CVE-2026-40683. The attack may be launched remotely. There is no exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in OpenStack Keystone up to 25.0.0/26.1.0/27.0.0/28.0.0 and classified as problematic. Affected by this issue is the function _ldap_res_to_model of the component Configuration Options Handler. The manipulation with an unknown input leads to a type confusion vulnerability. Using CWE to declare the problem leads to CWE-843. The product allocates or initializes a resource such as a pointer, object, or variable using one type, but it later accesses that resource using a type that is incompatible with the original type. Impacted is confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is shared for download at bugs.launchpad.net. This vulnerability is handled as CVE-2026-40683 since 04/14/2026. The exploitation is known to be difficult. The attack may be launched remotely. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 321365 (Ubuntu 22.04 LTS / 24.04 LTS / 25.10 / 26.04 LTS : OpenStack Keystone vulnerabilities (USN-8433-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 25.0.1, 26.1.1, 27.0.1 or 28.0.1 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (321365) and EUVD (EUVD-2026-22701). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.2

VulDB Base Score: 5.0
VulDB Temp Score: 4.8
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.7
CNA Vector (MITRE): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Type confusion
CWE: CWE-843
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 321365
Nessus Name: Ubuntu 22.04 LTS / 24.04 LTS / 25.10 / 26.04 LTS : OpenStack Keystone vulnerabilities (USN-8433-1)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Keystone 25.0.1/26.1.1/27.0.1/28.0.1

Timelineinfo

04/14/2026 Advisory disclosed
04/14/2026 +0 days CVE reserved
04/14/2026 +0 days VulDB entry created
08/06/2026 +114 days VulDB entry last update

Sourcesinfo

Vendor: openstack.org

Advisory: bugs.launchpad.net
Status: Confirmed

CVE: CVE-2026-40683 (🔒)
GCVE (CVE): GCVE-0-2026-40683
GCVE (VulDB): GCVE-100-357584
EUVD: 🔒

Entryinfo

Created: 04/14/2026 23:53
Updated: 08/06/2026 21:22
Changes: 04/14/2026 23:53 (65), 04/15/2026 05:52 (1), 06/19/2026 17:47 (2), 08/06/2026 21:22 (1)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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