Authentication Bypass in Bitwarden Server Affects API Key Management
CVE-2026-43640

8.6HIGH

Key Information:

Vendor

Bitwarden

Status
Server
Vendor
CVE Published:
11 May 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-43640?

Bitwarden Server versions prior to v2026.4.1 contain a critical flaw that allows authenticated users with SCIM management privileges to bypass the re-authentication requirement when accessing or rotating an organization's SCIM API key. This vulnerability enables unauthorized retrieval of sensitive API keys through a valid session, presenting significant risks to organizational security and data integrity.

Affected Version(s)

server 0

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-43640 - Proof of Concept

References

https://sanjokkarki.com.np/blog/bitwarden-scim-key-bypass
technical-descriptionexploit
https://github.com/bitwarden/server/releases/tag/v2026.4.1
release-notes
https://github.com/bitwarden/server/pull/7403
issue-tracking

CVSS V4

Score:
8.6
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

Sanjok Karki
.