CVE-2026-43639
Full vulnerability record from the local CVENow database.
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).
Severity
HIGH
CVSS score
8.9
(v4.0)
Vulnerability status
Analyzed
Source identifier
Published
2026-05-11 18:16:36.970000
Last modified
2026-10-26 18:10:00.173000
View original CVE JSON
{
"id": "CVE-2026-43639",
"sourceIdentifier": "[email protected]",
"published": "2026-05-11T18:16:36.970",
"lastModified": "2026-10-26T18:10:00.173",
"vulnStatus": "Analyzed",
"cveTags": [],
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"value": "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)."
},
{
"lang": "es",
"value": "Bitwarden Server anterior a la v2026.4.0 contiene una vulnerabilidad de autorización faltante que permite a un usuario del servicio de proveedor añadir una organización arbitraria a su proveedor a través de ’POST /providers/{providerId}/clients/existing’, lo que resulta en la toma de control de la organización objetivo; las instalaciones autoalojadas no se ven afectadas ya que este endpoint está restringido a la Nube a través de SelfHosted(NotSelfHostedOnly = true)."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "bitwarden",
"product": "server",
"defaultStatus": "affected",
"repo": "https://github.com/bitwarden/server",
"packageURL": "pkg:github/bitwarden/server",
"versions": [
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"lessThan": "2026.4.0",
"versionType": "semver",
"status": "affected"
}
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}
],
"metrics": {
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"baseScore": 8.9,
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"modifiedAttackVector": "NOT_DEFINED",
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"modifiedAttackRequirements": "NOT_DEFINED",
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"modifiedUserInteraction": "NOT_DEFINED",
"modifiedVulnConfidentialityImpact": "NOT_DEFINED",
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"modifiedVulnAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"valueDensity": "NOT_DEFINED",
"vulnerabilityResponseEffort": "NOT_DEFINED",
"providerUrgency": "NOT_DEFINED"
}
}
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"description": [
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"source": "[email protected]",
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{
"url": "https://github.com/bitwarden/server/releases/tag/v2026.4.0",
"source": "[email protected]",
"tags": [
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},
{
"url": "https://sanjokkarki.com.np/blog/bitwarden-provider-takeover",
"source": "[email protected]",
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{
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}