CVE-2026-28207 (GCVE-0-2026-28207)
Vulnerability from cvelistv5 – Published: 2026-02-26 22:17 – Updated: 2026-03-02 20:48
VLAI
EPSS
VEX
Title
Zen-C Vulnerable to Command Injection via Malicious Output Filename
Summary
Zen C is a systems programming language that compiles to human-readable GNU C/C11. Prior to version 0.4.2, a command injection vulnerability (CWE-78) in the Zen C compiler allows local attackers to execute arbitrary shell commands by providing a specially crafted output filename via the `-o` command-line argument. The vulnerability existed in the `main` application logic (specifically in `src/main.c`), where the compiler constructed a shell command string to invoke the backend C compiler. This command string was built by concatenating various arguments, including the user-controlled output filename, and was subsequently executed using the `system()` function. Because `system()` invokes a shell to parse and execute the command, shell metacharacters within the output filename were interpreted by the shell, leading to arbitrary command execution. An attacker who can influence the command-line arguments passed to the `zc` compiler (like through a build script or a CI/CD pipeline configuration) can execute arbitrary commands with the privileges of the user running the compiler. The vulnerability has been fixed in version 0.4.2 by removing `system()` calls, implementing `ArgList`, and internal argument handling. Users are advised to update to Zen C version v0.4.2 or later.
Severity
6.6 (Medium)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-02 20:48 UTC
CWE
- CWE-78 - Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
Assigner
GitHub_M
CNA
References
2 references
| URL | Tags |
|---|---|
| https://github.com/z-libs/Zen-C/security/advisori… | x_refsource_CONFIRM |
| https://f0nduesav0yarde.github.io/blog/vulnerabil… |
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