Bitwarden Server < 2026.4.0 Missing Authorization via Provider Clients
41Vexday Risk Score
No sign of exploitation. It has a public proof of concept.
ssvc Attendcvss 8.9epss 0.6%
exploitation probability
0.6%top 55% of all CVEs
observed exploitation
nono source reports it
1 public exploit(s)
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).
CVSS:4.0/AV:N/AC:H/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
Affected products
bitwarden · serverpublic PoCs found — 1
cve_referencesanjokkarki.com.np/blog/bitwarden-provider-takeoverunverified⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
References
https://github.com/bitwarden/server/commit/0918bfdda6f5eec391c69bd9074f6aef4eac0b1dhttps://github.com/bitwarden/server/pull/7372https://github.com/bitwarden/server/releases/tag/v2026.4.0https://sanjokkarki.com.np/blog/bitwarden-provider-takeoverhttps://www.vulncheck.com/advisories/bitwarden-server-missing-authorization-via-provider-clients