CVE-2026-19851 Overview
CVE-2026-19851 is a Use of Default Password vulnerability [CWE-1393] affecting Tuleap Enterprise Edition versions 17.0 through 17.5. User accounts created through the XML import process receive a predictable default password. Attackers can leverage this weakness to authenticate as imported users and access their accounts over the network without prior credentials.
Critical Impact
Unauthenticated network attackers can gain access to Tuleap user accounts created via XML import, leading to confidentiality and integrity compromise of project data and limited availability impact.
Affected Products
- Tuleap Enterprise Edition 17.0
- Tuleap Enterprise Edition versions 17.1 through 17.4
- Tuleap Enterprise Edition 17.5
Discovery Timeline
- 2026-08-25 - CVE-2026-19851 published to NVD
- 2026-08-25 - Last updated in NVD database
Technical Details for CVE-2026-19851
Vulnerability Analysis
Tuleap Enterprise Edition supports bulk provisioning of users and projects through XML import. During this workflow, the application assigns a default password to accounts that do not carry an explicit credential in the XML payload. Because the password is predictable and shared across imported accounts, an attacker who knows or discovers the default value can authenticate as any user created through this path.
The issue is classified under [CWE-1393: Use of Default Password]. Exploitation is remote and requires no authentication or user interaction. The high attack complexity reflects preconditions such as identifying imported accounts and reaching the authentication endpoint. Successful exploitation grants full account access, exposing project artifacts, source control integrations, and workflow configurations tied to the compromised user.
Root Cause
The root cause is the assignment of a static, well-known password during XML import instead of forcing credential generation, requiring a per-account secret in the import payload, or marking imported accounts as password-change-required at first login. Any account created without an explicit password inherits the same default value.
Attack Vector
An unauthenticated remote attacker enumerates or identifies Tuleap accounts provisioned through XML import and attempts authentication using the known default password. Successful login grants the attacker the privileges of the imported user, enabling access to project repositories, trackers, and documents governed by that account. Refer to the 3DS Security Advisory CVE-2026-19851 for vendor-provided technical detail.
Detection Methods for CVE-2026-19851
Indicators of Compromise
- Successful authentication events for user accounts recently created through XML import workflows.
- Login activity from unexpected source IP ranges or geographies targeting recently provisioned Tuleap accounts.
- Session activity on imported accounts before the legitimate user has completed onboarding.
Detection Strategies
- Correlate Tuleap authentication logs against the list of users provisioned by XML import to flag first-time logins from unusual sources.
- Alert on authentication attempts against multiple imported accounts from a single source within short time windows, indicating credential replay.
- Review audit trails for permission changes, SSH key additions, or personal access token creation on imported accounts.
Monitoring Recommendations
- Forward Tuleap application and authentication logs to a centralized SIEM for retention and correlation.
- Monitor XML import operations and record every account created, including provisioning source and initial password state.
- Track failed and successful logins per account and build a baseline for imported user behavior during the onboarding period.
How to Mitigate CVE-2026-19851
Immediate Actions Required
- Upgrade Tuleap Enterprise Edition to a fixed release above 17.5 as identified in the vendor advisory.
- Force password resets for every user account created through XML import on affected versions.
- Audit imported accounts for unauthorized logins, permission changes, and token generation since the account was provisioned.
Patch Information
Refer to the 3DS Security Advisory CVE-2026-19851 for the fixed version and upgrade guidance. Apply the vendor-supplied update to Tuleap Enterprise Edition to remove the default password behavior during XML import.
Workarounds
- Include explicit, unique passwords for every account in XML import payloads rather than relying on defaults.
- Disable or lock imported accounts until the intended user completes an out-of-band password reset.
- Restrict access to the Tuleap authentication endpoint through network controls until patching is complete.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
