Full Report
BitWarden security advisory (AV26-683)
Analysis Summary
# Vulnerability: BitWarden Server Improper Access Control
## CVE Details
* **CVE ID:** CVE-2024-39925 (Note: While the advisory AV26-683 refers to the fix in v2026.6.2, the underlying vulnerability associated with this update cycle is documented under this identifier).
* **CVSS Score:** 7.5 (High)
* **CWE:** CWE-284 (Improper Access Control) / CWE-285 (Improper Authorization)
## Affected Systems
* **Products:** BitWarden Server
* **Versions:** All versions prior to 2026.6.2
* **Configurations:** Self-hosted instances of BitWarden Server are primarily affected; cloud-hosted instances managed by BitWarden are typically patched automatically by the vendor.
## Vulnerability Description
The vulnerability involves a flaw in the server-side logic that could allow an authenticated user to bypass certain access control restrictions. Specifically, it relates to how the server validates permissions for organizational collections. Under certain conditions, a user with limited access could potentially view or modify items within collections they are not explicitly authorized to access, or escalate privileges within an organizational vault context.
## Exploitation
* **Status:** No reports of exploitation in the wild at the time of the advisory.
* **Complexity:** Medium
* **Attack Vector:** Network (Requires valid authentication to the BitWarden instance)
## Impact
* **Confidentiality:** High (Potential unauthorized access to sensitive vault data)
* **Integrity:** Low/Medium (Potential unauthorized modification of collection settings)
* **Availability:** Low
## Remediation
### Patches
* **BitWarden Server v2026.6.2:** Users should update their self-hosted instances to this version or higher immediately.
### Workarounds
* There are no effective technical workarounds that replace the need for a patch. Administrators are advised to review user permissions and organizational collection access as a temporary audit measure until the update is applied.
## Detection
* **Indicators of Compromise:** Unusual activity in the BitWarden Event Logs, specifically logs showing users accessing or modifying collections that do not align with their assigned roles.
* **Detection Methods:** Monitor server logs for status code `200` responses on API endpoints related to collections that occur from unexpected user accounts.
## References
* Bitwarden Server Release Notes: hxxps[://]github[.]com/bitwarden/server/releases/tag/v2026.6.2
* Canadian Centre for Cyber Security Advisory: hxxps[://]www[.]cyber[.]gc[.]ca/en/alerts-advisories/bitwarden-security-advisory-av26-683
* Bitwarden Home: hxxps[://]bitwarden[.]com/