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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-43639 Detail

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).


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  VulnCheck
CVSS-B 8.9 HIGH
Vector:  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

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/bitwarden/server/commit/0918bfdda6f5eec391c69bd9074f6aef4eac0b1d VulnCheck Patch 
https://github.com/bitwarden/server/pull/7372 VulnCheck Issue Tracking  Patch 
https://github.com/bitwarden/server/releases/tag/v2026.4.0 VulnCheck Release Notes 
https://sanjokkarki.com.np/blog/bitwarden-provider-takeover VulnCheck Exploit  Third Party Advisory 
https://www.vulncheck.com/advisories/bitwarden-server-missing-authorization-via-provider-clients VulnCheck Third Party Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-862 Missing Authorization VulnCheck  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

4 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-43639
NVD Published Date:
05/11/2026
NVD Last Modified:
06/17/2026
Source:
VulnCheck