CVE-2026-101878 (GCVE-0-2026-101878)

Vulnerability from cvelistv5 – Published: 2026-09-29 01:58 – Updated: 2026-10-01 19:19 X_Open Source
VLAI
Title
Bitwarden Server 2025.6.0 < 2025.6.0 Authentication Bypass via SSO Identifier Truncation
Summary
Bitwarden Server 2025.6.0 before 2026.5.0 declares the @ExternalId parameter of the User_ReadBySsoUserOrganizationIdExternalId stored procedure as NVARCHAR(50) while the column it queries stores NVARCHAR(300), silently truncating the SSO login identifier on SQL Server deployments and allowing a user whose identity-provider identifier begins with another organization member's full 50-character identifier to authenticate as that member and obtain a victim-scoped access token.
Severity
7.7 (High)
CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
7.5 (High)
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-29 17:21 UTC
CWE
  • CWE-303 - Incorrect Implementation of Authentication Algorithm
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 6637 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
bitwarden bitwarden server Affected: 2025.6.0 , < 2026.5.0 (custom)
    cpe:2.3:a:bitwarden:server:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-04-29 00:00
Credits
Sanjok Karki
Show details on NVD website
To clipboard 

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