CVE-2026-43638

Bitwarden Server prior to v2026.4.1 contains a missing authorization vulnerability that allows any authenticated user to write ciphers into an arbitrary organization via `POST /ciphers/import-organization` by submitting an empty `collections` array, which causes the server-side permission check to be skipped.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/bitwarden/server/commit/ebbf6dd0fa752114c09d73abb48ce32a50476758	Patch
https://github.com/bitwarden/server/pull/7394	Issue Tracking Patch
https://github.com/bitwarden/server/releases/tag/v2026.4.1	Release Notes
https://sanjokkarki.com.np/blog/bitwarden-import-org-bypass	Exploit Third Party Advisory
https://www.vulncheck.com/advisories/bitwarden-server-missing-authorization-via-organization-cipher-import	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:bitwarden:server:*:*:*:*:*:*:*:*

History

26 Oct 2026, 18:10

Type	Values Removed	Values Added
Summary		(es) El servidor Bitwarden anterior a la v2026.4.1 contiene una vulnerabilidad de autorización faltante que permite a cualquier usuario autenticado escribir cifrados en una organización arbitraria a través de ’POST /ciphers/import-organization’ al enviar una matriz ’collections’ vacía, lo que provoca que la comprobación de permisos del lado del servidor se omita.

Information

Published : 2026-05-11 18:16

Updated : 2026-10-26 18:10

NVD link : CVE-2026-43638

Mitre link : CVE-2026-43638

CVE.ORG link : CVE-2026-43638

JSON object : View

Products Affected

bitwarden

server

CWE

CWE-862

Missing Authorization

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