CVE-2026-27701 is a critical code injection vulnerability classified under CWE-94 affecting LiveCode, an open-source client-side code playground. The vulnerability resides in the `i18n-update-pull` GitHub Actions workflow, specifically in how it handles the title of pull requests. Before the fix, the PR title was directly interpolated into a JavaScript block executed by the `actions/github-script` action without proper sanitization or validation. This unsafe interpolation allows an attacker who creates a pull request with a specially crafted title to inject arbitrary JavaScript code. The injected code runs with the privileges of the CI bot token, which includes `CI_APP_ID` and `CI_APP_PRIVATE_KEY`. These credentials provide elevated access to the repository, enabling the attacker to exfiltrate sensitive repository secrets and perform unauthorized operations via the GitHub API. The vulnerability requires an attacker to open a pull request, thus involving user interaction, and has a high attack complexity due to the need to craft a valid PR title that triggers the injection. The issue was resolved in commit e151c64c2bd80d2d53ac1333f1df9429fe6a1a11 by sanitizing the input or changing how the PR title is handled in the workflow. No public exploits have been reported so far, but the potential impact is significant given the access level of the CI token. This vulnerability highlights the risks of improper input handling in CI/CD workflows and the importance of securing automation scripts that interact with external inputs.

The impact of CVE-2026-27701 is substantial for organizations using LiveCode with the vulnerable GitHub Actions workflow. Successful exploitation allows attackers to execute arbitrary JavaScript code with the privileges of the CI bot token, which can lead to the theft of repository secrets such as API keys, credentials, and other sensitive data stored in GitHub secrets. Unauthorized GitHub API operations could include modifying repository contents, creating or merging pull requests, or disrupting CI/CD pipelines. This can compromise the integrity and confidentiality of the software development lifecycle, potentially leading to supply chain attacks or unauthorized code changes. The vulnerability could also damage organizational reputation and trust if source code or secrets are leaked. Since the attack requires opening a pull request, organizations with open or public repositories accepting external contributions are at higher risk. The high CVSS score of 8.8 reflects the critical nature of the vulnerability, combining high impact with moderate attack complexity.

To mitigate CVE-2026-27701, organizations should immediately update LiveCode to include the fix introduced in commit e151c64c2bd80d2d53ac1333f1df9429fe6a1a11 or later. Review and sanitize all inputs used in GitHub Actions workflows, especially those interpolated into scripts or commands, to prevent code injection. Implement strict validation and escaping of pull request titles or any user-generated content before usage in automation scripts. Limit the scope and permissions of CI bot tokens to the minimum necessary, employing the principle of least privilege to reduce potential damage from token compromise. Monitor repository activity for unusual pull requests or workflow executions, and audit GitHub secrets usage and access logs for anomalies. Consider using GitHub’s security features such as branch protection rules and required reviews to control pull request merges. Finally, educate development teams about the risks of injecting untrusted input into CI/CD pipelines and encourage secure coding practices in automation workflows.