CVE-2026-57520

Description

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.

References

• https://github.com/bitwarden/server/commit/901bb67157c0f80d369c40b76742fdf7623da4e4
• https://github.com/bitwarden/server/pull/7526
• https://github.com/bitwarden/server/releases/tag/v2026.5.0
• https://sanjokkarki.com.np/blog/bitwarden-bulk-remove-admin
• https://www.vulncheck.com/advisories/bitwarden-server-privilege-escalation-via-bulk-user-remove-endpoint