CVE-2024-58354 in cal.diy
Summary
by MITRE • 07/24/2026
cal.com (calcom repository, later renamed cal.diy) is affected by a repository takeover vulnerability in its GitHub Actions workflows. The workflow pr.yml uses the pull_request_target trigger with the repository's default write permissions and passes them down to check-types.yml. check-types.yml then performs a 'dangerous' checkout of the attacker-submitted pull request code (via the dangerous-git-checkout action) and subsequently executes it (through yarn install and package.json scripts). An attacker can open a pull request whose code runs arbitrary commands with the repository's write-scoped GITHUB_TOKEN, allowing them to push commits, merge or mutate pull requests, add or delete comments, and delete or force-push branches, thereby compromising the repository. The main branch is affected; no patched version is available.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 07/24/2026
The vulnerability in cal.com represents a critical supply chain attack vector through GitHub Actions workflow misconfiguration that aligns with CWE-470 and CWE-94. This repository takeover occurs due to improper use of the pull_request_target trigger which executes workflows in the context of the base repository rather than the forked pull request, creating an inherent security risk when combined with elevated permissions. The workflow architecture creates a dangerous execution path where the default write permissions granted to the GITHUB_TOKEN are passed through multiple workflow layers without proper isolation or sanitization.
The technical flaw manifests in how check-types.yml executes attacker-controlled code through the dangerous-git-checkout action, which directly executes arbitrary commands from pull request submissions. This pattern violates fundamental security principles of least privilege and code isolation, as demonstrated by ATT&CK technique T1059.001 for executing malicious code and T1531 for privilege escalation through automation. The workflow chain allows untrusted code execution with repository-level write permissions, effectively granting attackers complete control over the repository's contents and history.
Operational impact of this vulnerability extends far beyond simple code execution, as demonstrated by ATT&CK technique T1098.001 for account manipulation and T1486 for data destruction. Attackers can push commits to any branch, merge malicious changes into main, modify or delete existing pull requests, add spam comments, and perform destructive operations like force-pushing branches or deleting entire repositories. The absence of a patched version and the fact that the main branch is affected means organizations using this codebase are immediately vulnerable without any remediation path.
Mitigation strategies must address both immediate workflow fixes and long-term architectural improvements. Organizations should implement proper isolation by avoiding pull_request_target triggers for workflows requiring elevated permissions, instead using pull_request events with restricted permissions. The dangerous-git-checkout action should be replaced with standard checkout operations that don't execute arbitrary code. Additionally, implementing GitHub Actions security controls such as repository dispatch restrictions, workflow permissions enforcement, and code scanning integrations would prevent similar vulnerabilities. Defense in depth requires configuring secrets management properly, implementing branch protection rules, and establishing automated monitoring for unauthorized changes to critical workflows. The vulnerability demonstrates the importance of following supply chain security best practices and aligns with NIST SP 800-171 requirements for protecting against unauthorized access and privilege escalation through automation frameworks.