PT-2026-102434 · Bitwarden · Bitwarden Server

·

CVE-2026-101878

·

Published

2026-09-29

·

Updated

2026-09-29

CVSS v3.1

7.5

High

VectorAV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Name of the Vulnerable Software and Affected Versions Bitwarden Server versions 2025.6.0 through 2026.4.x
Description In SQL Server deployments, the stored procedure User ReadBySsoUserOrganizationIdExternalId() declares the @ExternalId parameter as NVARCHAR(50), whereas the queried column uses NVARCHAR(300). This discrepancy causes the SSO login identifier to be silently truncated. Consequently, a user whose identity-provider identifier starts with the full 50-character identifier of another organization member can authenticate as that member and obtain a victim-scoped access token.
Recommendations Update Bitwarden Server to version 2026.5.0 or later.

Exploit

Fix

Found an issue in the description? Have something to add? Feel free to write us 👾

Weakness Enumeration

Related Identifiers

CVE-2026-101878

Affected Products

Bitwarden Server