Description

Jenkins LDAP Plugin 807.809.vd3a_4e5e4ec98 and earlier allows connecting to a specified URL through Stapler data binding, allowing attackers to connect to an attacker-specified URL.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "4.3",
  "pubDate": "2026-09-02T16:17:30.857Z",
  "pubdate": "2026-09-02T16:17:30.857Z",
  "executiveSummary": "The Jenkins LDAP Plugin, in versions 807.809.vd3a_4e5e4ec98 and earlier, is susceptible to a Server-Side Request Forgery (SSRF) vulnerability. This flaw arises from improper handling of Stapler data binding, which allows remote attackers to force the Jenkins server to initiate outbound connections to arbitrary, attacker-controlled URLs.\nThe vulnerability allows an adversary to interact with internal network resources or external services under the identity of the Jenkins server. By manipulating the request parameters processed by the plugin, an attacker can bypass network access controls, perform reconnaissance on internal infrastructure, or leverage the server as a proxy for further malicious activities. Given the critical role of Jenkins in continuous integration/continuous deployment (CI/CD) pipelines, unauthorized access to internal resources poses a significant risk to the integrity and confidentiality of the development environment.\nSuccessful exploitation requires the ability to reach the vulnerable endpoint, though specific authentication requirements may vary based on the Jenkins instance configuration. Organizations utilizing the affected LDAP plugin versions are encouraged to restrict network exposure and evaluate updates to mitigate this SSRF vector.",
  "technicalDetails": "The root cause of the vulnerability resides in the insecure implementation of Stapler data binding within the Jenkins LDAP Plugin. Stapler is the core web framework used by Jenkins, which automatically maps HTTP request parameters to Java object properties. In this instance, the plugin fails to properly validate or sanitize the input designated for the LDAP server URL configuration.\nWhen an attacker crafts a malicious request targeting the plugin's configuration endpoint, the Stapler data binding mechanism populates the internal LDAP server configuration object with user-supplied data. Because the plugin does not enforce strict validation on the URL field, it accepts arbitrary strings, including malicious URLs pointing to internal services (e.g., http://localhost:8080/ or internal cloud metadata services) or external malicious servers.\nThe attack flow follows a structured exploitation path. First, the attacker identifies a reachable Jenkins instance with the vulnerable LDAP plugin enabled. Second, the attacker sends a crafted POST request to the administrative or configuration endpoint managed by the plugin. This request leverages the Stapler data binding to overwrite the LDAP server URL property. Third, the plugin initiates an outbound network request to the specified, attacker-provided URL to perform a connectivity check or validate the LDAP configuration. Because the request originates from the Jenkins process itself, the outbound connection possesses the server's network identity and permissions.\nThe impact of this SSRF is multi-faceted. Attackers can perform port scanning on the Jenkins host or adjacent network segments that are otherwise isolated from public access. Furthermore, if the Jenkins server is hosted in cloud environments, such as AWS, GCP, or Azure, the attacker may be able to query the instance metadata service (IMDS) via the SSRF vector to exfiltrate sensitive credentials, security tokens, or environment-specific configuration details. The lack of validation at the point of ingestion allows this primitive to be used for bypasses of firewall rules and potentially exfiltration of data protected by internal-only network policies.\nThis vulnerability affects Jenkins LDAP Plugin version 807.809.vd3a_4e5e4ec98 and all versions preceding it. Exploitation is facilitated by the plugin's inherent functionality to verify LDAP connections, which effectively acts as the execution trigger for the SSRF. System administrators must identify whether the Jenkins instance exposes configuration endpoints to unauthenticated or unauthorized users, as this significantly influences the immediate threat landscape."
}