CVE-2026-43639

Summary

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 Software

VendorProductVersion RangeStatus
bitwardenserver0 < 2026.4.0affected

Weaknesses

  • CWE-862: Missing Authorization

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: poc
    • Automatable: no
    • Technical Impact: total

References