CVE-2026-57520

Bitwarden Server before 2026.5.0 contains a privilege escalation vulnerability that allows authenticated Custom users with ManageUsers permission to remove Admin accounts from an organization by exploiting a missing role hierarchy check in the bulk user-remove endpoint. Attackers can supply Admin organization-user IDs in a bulk DELETE request to bypass the guard enforced on the single-user removal path, effectively removing one or more Admin accounts from an organization.

CVSS v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/bitwarden/server/commit/901bb67157c0f80d369c40b76742fdf7623da4e4	Patch
https://github.com/bitwarden/server/pull/7526	Issue Tracking
https://github.com/bitwarden/server/releases/tag/v2026.5.0	Release Notes
https://sanjokkarki.com.np/blog/bitwarden-bulk-remove-admin	Exploit Patch Third Party Advisory
https://www.vulncheck.com/advisories/bitwarden-server-privilege-escalation-via-bulk-user-remove-endpoint	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:bitwarden:server:*:*:*:*:*:*:*:*

History

25 Oct 2026, 22:10

Type	Values Removed	Values Added
Summary		(es) Bitwarden Server anterior a 2026.5.0 contiene una vulnerabilidad de escalada de privilegios que permite a usuarios personalizados autenticados con permiso ManageUsers eliminar cuentas de administrador de una organización explotando una comprobación de jerarquía de roles ausente en el endpoint de eliminación masiva de usuarios. Los atacantes pueden proporcionar IDs de usuario de organización de administrador en una solicitud DELETE masiva para eludir la protección aplicada en la ruta de eliminación de usuario único, eliminando efectivamente una o más cuentas de administrador de una organización.

Information

Published : 2026-06-25 20:17

Updated : 2026-10-25 22:10

NVD link : CVE-2026-57520

Mitre link : CVE-2026-57520

CVE.ORG link : CVE-2026-57520

JSON object : View

Products Affected

bitwarden

server

CWE

CWE-862

Missing Authorization

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