CVE-2026-101878

What it is

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.

At a glance

Exploitability

Can be exploited over the network with a low-privilege account. High risk of data exposure, data tampering, service disruption.

Exploit odds

0.3% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-09-29 02:16 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-09-30 17:23 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 0.3% in the next 30 days (EPSS).
• Severity: 7.7 HIGH (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2026-09-29 02:16 UTC

Last modified

2026-09-30 17:23 UTC

Exploit probability

0.3% · EPSS, next 30 days

Weakness

CWE-303

Record status

Awaiting Analysis

Attack profile CVSS 4.0 · 7.7

Attack vector

Network

Complexity

High

Attack requirements

None

Privileges needed

Low

User interaction

None

Confidentiality

High

Integrity

High

Availability

High

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2026-101878.md and follow it. Check whether this project is affected by CVE-2026-101878. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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