CVE-2022-43407 is a high-severity vulnerability affecting the Jenkins Pipeline: Input Step Plugin, specifically versions 451.vf1a_a_4f405289 and earlier. The vulnerability arises because the plugin does not properly restrict or sanitize the optionally specified ID parameter of the 'input' step. This ID is used in URLs that handle user interactions such as proceeding or aborting the input step within Jenkins pipelines. Due to improper encoding and lack of validation, an attacker with the ability to configure Jenkins pipelines can craft malicious 'input' step IDs that generate URLs bypassing Jenkins' Cross-Site Request Forgery (CSRF) protections. This bypass allows attackers to perform unauthorized actions by tricking legitimate users into interacting with malicious URLs, potentially leading to unauthorized pipeline executions or modifications. The vulnerability is classified under CWE-352 (Cross-Site Request Forgery) and has a CVSS v3.1 score of 8.8, indicating a high impact on confidentiality, integrity, and availability. Exploitation requires no privileges (PR:N) but does require user interaction (UI:R), such as clicking a crafted link. The vulnerability affects Jenkins instances that use the Input Step Plugin and allow pipeline configuration by potentially untrusted users or collaborators. No known exploits in the wild have been reported yet, but the severity and ease of exploitation make it a significant risk for affected environments.

For European organizations relying on Jenkins for continuous integration and continuous deployment (CI/CD), this vulnerability poses a serious risk. Successful exploitation could allow attackers to bypass CSRF protections and manipulate pipeline executions, potentially leading to unauthorized code deployments, exposure of sensitive build information, or disruption of development workflows. This could compromise the integrity of software supply chains, leading to the introduction of malicious code or backdoors in production systems. The impact extends to confidentiality, as sensitive build parameters or credentials might be exposed, and availability, as pipeline disruptions could delay critical software releases. Organizations in sectors with stringent regulatory requirements, such as finance, healthcare, and critical infrastructure, may face compliance violations and reputational damage if exploited. The requirement for user interaction means social engineering or phishing tactics could be employed to trigger the vulnerability, increasing the attack surface in collaborative environments.

To mitigate this vulnerability, European organizations should: 1) Immediately update the Jenkins Pipeline: Input Step Plugin to the latest patched version once available from the official Jenkins project, as no patch links were provided in the initial report but should be monitored. 2) Restrict pipeline configuration permissions strictly to trusted users to prevent untrusted actors from injecting malicious 'input' step IDs. 3) Implement network segmentation and access controls to limit exposure of Jenkins instances to only necessary personnel and systems. 4) Educate users about phishing and social engineering risks to reduce the likelihood of user interaction exploitation. 5) Monitor Jenkins logs and pipeline activities for unusual or unauthorized input step interactions that could indicate exploitation attempts. 6) Consider deploying Web Application Firewalls (WAFs) with rules to detect and block suspicious URL patterns related to the input step IDs. 7) Review and harden CSRF protections and ensure Jenkins and all plugins are kept up to date with security patches. 8) If possible, disable or limit the use of the Input Step Plugin in pipelines where it is not essential.