CVE-2026-28207 (GCVE-0-2026-28207)

Vulnerability from cvelistv5 – Published: 2026-02-26 22:17 – Updated: 2026-03-02 20:48
VLAI
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)
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:L
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-78 - Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
Assigner
References
Impacted products
Vendor Product Version
z-libs Zen-C Affected: < 0.4.2
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.