CVE-2025-47888 is a vulnerability identified in the Jenkins DingTalk Plugin version 2.7.3 and earlier. The core issue is that the plugin unconditionally disables SSL/TLS certificate and hostname validation when establishing connections to configured DingTalk webhooks. This means that the plugin does not verify the authenticity of the server it is communicating with, allowing an attacker to perform man-in-the-middle (MITM) attacks by intercepting or spoofing the webhook communication channel. The vulnerability is classified under CWE-20 (Improper Input Validation), as it involves the plugin failing to properly validate critical security parameters during network communication. The CVSS v3.1 base score is 5.9, indicating a medium severity level. The vector string (AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:N) shows that the attack is network-based, requires low privileges, no user interaction, and has high impact on confidentiality, limited impact on integrity, and no impact on availability. Exploiting this vulnerability could allow an attacker to eavesdrop on sensitive information sent to DingTalk webhooks or inject malicious data, potentially leading to information disclosure or partial data manipulation within Jenkins pipelines that rely on DingTalk notifications. No known exploits in the wild have been reported yet, and no patches have been linked at the time of publication. The vulnerability affects all versions up to and including 2.7.3 of the Jenkins DingTalk Plugin. Given Jenkins' widespread use in continuous integration and deployment environments, this vulnerability poses a risk to the confidentiality of webhook communications and the integrity of notifications or commands sent via DingTalk integrations.

For European organizations, this vulnerability could have significant implications, especially for those using Jenkins for CI/CD pipelines integrated with DingTalk for notifications or automation. The lack of SSL/TLS validation exposes sensitive webhook communications to interception or tampering, potentially leaking confidential project information or allowing attackers to manipulate build or deployment notifications. This could lead to unauthorized disclosure of proprietary code, project status, or internal operational details. Although the vulnerability does not directly impact system availability, the compromise of confidentiality and partial integrity could undermine trust in automated processes and lead to further exploitation or lateral movement within networks. Organizations in regulated industries such as finance, healthcare, and critical infrastructure in Europe must be particularly cautious, as data leakage or manipulation could violate compliance requirements like GDPR or sector-specific regulations. The medium severity rating suggests that while exploitation requires some conditions (network access, low privileges), the risk is non-trivial and warrants timely remediation to prevent potential escalation or combined attacks.

To mitigate this vulnerability, European organizations should immediately audit their Jenkins environments to identify usage of the DingTalk Plugin version 2.7.3 or earlier. Until an official patch is released, organizations should consider disabling the DingTalk Plugin or removing webhook configurations that rely on it to prevent exposure. If webhook functionality is critical, organizations can implement network-level protections such as restricting Jenkins server outbound connections to only trusted DingTalk endpoints via firewall rules or proxy configurations. Additionally, organizations should monitor network traffic for unusual patterns indicative of MITM attempts. Once a patched version is available, prompt updating of the plugin is essential. As a longer-term measure, organizations should enforce strict SSL/TLS validation in all webhook or API integrations and conduct regular security reviews of third-party plugins. Implementing mutual TLS authentication for webhook endpoints, if supported, can further enhance security. Finally, educating DevOps teams about the risks of disabling certificate validation and encouraging secure plugin configuration practices will help prevent similar issues.