Description
Bitwarden Server prior to v2026.4.0 contains a missing authorization vulnerability that allows a provider service user to add an arbitrary organization to their provider via `POST /providers/{providerId}/clients/existing`, resulting in takeover of the target organization; self-hosted installations are unaffected as this endpoint is restricted to Cloud via SelfHosted(NotSelfHostedOnly = true).
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
bitwarden server
Default version status: affected
0 to < 2026.4.0affected
pkg:github/bitwarden/serverReferences
- https://sanjokkarki.com.np/blog/bitwarden-provider-takeover ↗
- https://github.com/bitwarden/server/releases/tag/v2026.4.0 ↗
- https://github.com/bitwarden/server/pull/7372 ↗
- https://github.com/bitwarden/server/commit/0918bfdda6f5eec391c69bd9074f6aef4eac0b1d ↗
- https://www.vulncheck.com/advisories/bitwarden-server-missing-authorization-via-provider-clients ↗