How to remediate – Jira Service Desk Sign Up Detected

1. Introduction

Jira Service Desk Sign Up Detected refers to a misconfiguration in Atlassian Jira, where an internal service desk instance is accessible for public sign-ups. This allows attackers to create accounts and potentially request privileged access, exposing sensitive information like email addresses contained within tickets. Confidentiality, integrity, and availability may be compromised if exploited.

2. Technical Explanation

The vulnerability occurs when Jira Service Desk instances are not properly restricted to internal users only. Attackers can exploit this by signing up for accounts on publicly accessible instances, potentially gaining access to sensitive data or escalating privileges through ticket requests. The primary root cause is insufficient access control configuration. An example attack involves an attacker creating a user account and submitting support tickets designed to reveal internal information or gain unauthorized system access.

• Root cause: Incorrectly configured customer permissions allowing external sign-ups.
• Exploit mechanism: Attackers register accounts on open Jira Service Desk instances, then submit requests for sensitive data or privileged access.
• Scope: Atlassian Jira Service Desk instances misconfigured with public signup enabled.

3. Detection and Assessment

To confirm vulnerability, first check if external sign-up is permitted on the instance. A thorough assessment involves reviewing customer permissions settings within Jira.

• Quick checks: Access the Jira Service Desk registration page to see if public signup is enabled.
• Scanning: No specific scanner signatures are available for this misconfiguration, but general web application scanners may identify open registration forms.
• Logs and evidence: Review Jira audit logs for account creation events from unknown or external email domains.

# There is no command to run here. Check the registration page directly in a browser.

4. Solution / Remediation Steps

The following steps restrict access permissions to prevent unauthorized account creation and potential exploitation.

4.1 Preparation

• Dependencies: Access to the Jira Service Desk administration settings is required. Rollback involves restoring the previous permissions configuration.
• Change window needs and approval may be needed depending on internal policies.

4.2 Implementation

1. Step 1: Log in to the Atlassian Jira Service Desk instance as an administrator.
2. Step 2: Navigate to Project settings > Customer permissions.
3. Step 3: Ensure “Anyone” is not selected for any permission that allows account creation or ticket submission. Restrict access to authenticated users only, or specific groups.
4. Step 4: Verify the changes by attempting to sign up with an external email address. It should be blocked.

4.3 Config or Code Example

Before

Allow anyone to register: Enabled

After

Allow only logged in users to register: Enabled

4.4 Security Practices Relevant to This Vulnerability

Several security practices can help prevent this issue. Least privilege reduces the impact of compromised accounts. Input validation prevents malicious data from being submitted. Secure defaults ensure that systems are configured securely out-of-the-box.

• Practice 1: Implement least privilege to limit access rights for all users, reducing potential damage if an account is compromised.
• Practice 2: Regularly review and update customer permissions settings to ensure they align with the principle of least privilege.

4.5 Automation (Optional)

Automation scripts are not typically suitable for this vulnerability due to its configuration-based nature. However, infrastructure-as-code tools could be used to enforce consistent permission settings across multiple Jira instances.

# No automation script provided as it is a config change.

5. Verification / Validation

Confirm the fix by attempting to sign up with an external email address and verifying that registration is blocked. A service smoke test should confirm existing users can still submit tickets.

• Post-fix check: Attempting to register using a non-internal email address should result in an error message indicating access is denied.
• Re-test: Repeat the initial detection steps (attempting external sign-up) and verify that it is no longer possible.
• Smoke test: Log in as a valid internal user and submit a test ticket to confirm functionality remains intact.
• Monitoring: Review Jira audit logs for failed registration attempts from unknown email domains, which could indicate ongoing attacks.

# Expected output when attempting external signup: "You do not have permission to register."

6. Preventive Measures and Monitoring

Regular security baselines can prevent this issue by enforcing secure default configurations. CI/CD pipelines should include checks for misconfigured permissions settings. A sensible patch or config review cycle ensures timely updates.

• Baselines: Update a Jira security baseline to enforce restricted customer permissions.
• Pipelines: Add automated checks in deployment pipelines to verify that external sign-up is disabled on new instances.
• Asset and patch process: Implement a regular review cycle (e.g., quarterly) for Jira configuration settings, including customer permissions.

7. Risks, Side Effects, and Roll Back

Changing customer permissions could potentially disrupt legitimate users if misconfigured. The roll back steps involve restoring the previous permission settings from a backup or configuration history.

• Risk or side effect 1: Incorrectly configured permissions may prevent valid internal users from accessing the service desk.
• Risk or side effect 2: Changes to customer permissions could require updating documentation and user training materials.
• Roll back: Restore the previous Jira configuration settings from a backup, or manually revert the changes made in step 4.2.

8. References and Resources

Links only to sources that match this exact vulnerability.

• Vendor advisory or bulletin: https://medium.com/@intideceukelaire/hundreds-of-internal-servicedesks-exposed-due-to-covid-19-ecd0baec87bd
• NVD or CVE entry: No specific CVE is associated with this misconfiguration, but it relates to general access control issues.
• Product or platform documentation relevant to the fix: https://support.atlassian.com/jira-service-management-cloud/docs/customer-permissions-for-your-service-project-and-jira-site/