CVE-2026-25063 is an OS command injection vulnerability classified under CWE-78 and CWE-157, affecting the gradle-completion Bash script component of Gradle up to version 9.3.0. Gradle-completion provides shell completion support for Gradle commands, enhancing developer productivity by enabling tab completion of tasks and options. The vulnerability stems from improper neutralization of special elements in task names and descriptions when displayed during Bash tab completion. Specifically, if a Gradle build file contains a task description with a string enclosed in backticks, the Bash completion script evaluates this string as a shell command during tab completion. This leads to arbitrary command execution in the context of the user triggering the completion. The vulnerability does not require the user to explicitly run any Gradle task; merely triggering tab completion in a project with a malicious build file suffices. The flaw is limited to Bash completion and does not impact Zsh. Exploitation requires local access and user interaction (tab completion). The vulnerability was patched in gradle-completion version 9.3.1 by properly sanitizing task names and descriptions to prevent command injection. No known exploits are reported in the wild as of the publication date. The CVSS 4.0 vector indicates local attack vector, low attack complexity, no privileges required beyond local user, user interaction required, and high impact on confidentiality, integrity, and availability. This vulnerability poses a significant risk in development and build environments where Gradle is used with Bash completion enabled.

For European organizations, this vulnerability poses a substantial risk primarily in software development environments, continuous integration/continuous deployment (CI/CD) pipelines, and developer workstations where Gradle is used with Bash completion enabled. Successful exploitation can lead to arbitrary code execution with the privileges of the user running the shell, potentially allowing attackers to execute malicious commands, escalate privileges, or move laterally within internal networks. This could compromise source code integrity, leak sensitive intellectual property, or disrupt build processes. Organizations relying heavily on Gradle for Java or Android development, especially those with automated build systems that use Bash shells, are particularly vulnerable. The impact extends to any environment where developers or automated systems perform tab completion on Gradle commands. Given the high CVSS score, the vulnerability could facilitate supply chain attacks or insider threats if exploited. However, the requirement for local access and user interaction limits remote exploitation, reducing the risk of widespread automated attacks. Nonetheless, the potential for damage in targeted attacks against critical software development infrastructure in Europe is significant.

1. Upgrade gradle-completion to version 9.3.1 or later immediately to apply the official patch that properly sanitizes task names and descriptions. 2. As an interim measure, disable Bash completion for Gradle by removing or commenting out the gradle-completion script invocation in user shell initialization files such as .bashrc or .bash_profile. 3. Educate developers and build engineers about the risks of opening or working in projects with untrusted or unknown Gradle build files, especially when using Bash completion. 4. Implement strict access controls and code review policies to prevent malicious Gradle build files from entering source repositories or build environments. 5. Monitor developer workstations and CI/CD systems for unusual command execution or shell activity that could indicate exploitation attempts. 6. Consider restricting local user permissions and employing endpoint detection and response (EDR) solutions to detect anomalous behavior related to shell command execution. 7. Encourage use of alternative shells like Zsh for Gradle completion, as this vulnerability does not affect Zsh completion scripts. 8. Regularly audit and update development tools and dependencies to minimize exposure to known vulnerabilities.