Overview
In this blog post, we will be discussing a crucial security vulnerability identified as CVE-2025-47889. This vulnerability resides in the Jenkins WSO2 Oauth Plugin version 1.0 and earlier. The flaw enables unauthenticated attackers to bypass authentication measures and gain unauthorized access to controllers. This vulnerability is of particular concern to organizations and businesses that utilize Jenkins for their continuous integration/continuous deployment (CI/CD) processes, as it poses a significant threat to system integrity and data security.
Vulnerability Summary
CVE ID: CVE-2025-47889
Severity: Critical, CVSS Score 9.8
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: Potential system compromise or data leakage
Affected Products
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Product | Affected Versions
Jenkins WSO2 Oauth Plugin | 1.0 and earlier
How the Exploit Works
The exploit takes advantage of the lack of proper authentication validation in the WSO2 Oauth Plugin used by Jenkins. In specific, the “WSO2 Oauth” security realm accepts authentication claims without appropriate validation. This flaw allows an unauthenticated attacker to log in to a controller using this security realm with any username and password, including non-existent usernames. Essentially, this vulnerability provides an open door for attackers to access and potentially control the system without legitimate credentials.
Conceptual Example Code
In the given context, an attacker could simply send a POST request to the authentication endpoint with any username and password. For instance:
POST /oauth/authenticate HTTP/1.1
Host: target.example.com
Content-Type: application/json
{
"username": "nonexistentUser",
"password": "anyPassword"
}After the request is made, due to the vulnerability, the server would accept the authentication claims and grant access to the attacker.
Recommended Mitigations
To mitigate the risk of this vulnerability, it is recommended to apply the vendor patch as soon as it is available. In the meantime, using Web Application Firewalls (WAF) or Intrusion Detection Systems (IDS) can provide temporary mitigation by monitoring and potentially blocking malicious attempts to exploit this vulnerability. It is also advisable to regularly review and update security policies and practices to ensure they include the latest preventive measures against such threats.