Description

Improper neutralization of special elements used in an OS command in yast2-samba-client allows an attacker who controls the content of an Active Directory directory tree - a rogue domain controller, or a directory user delegated the right to create objects - to execute arbitrary commands as root on a machine being joined to that domain. This issue affects yast2-samba-client through 5.0.4.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.5",
  "pubDate": "2026-09-01T10:17:12.993Z",
  "pubdate": "2026-09-01T10:17:12.993Z",
  "executiveSummary": "The yast2-samba-client package is susceptible to an OS command injection vulnerability resulting from improper neutralization of special elements within OS commands.\nThis vulnerability resides in the domain joining process and affects versions up to 5.0.4.\nAn attacker who maintains control over an Active Directory (AD) directory tree—such as a rogue domain controller or an authenticated directory user with delegated object creation permissions—can exploit this flaw.\nBy manipulating malicious input within the directory structure, an attacker can trigger the execution of arbitrary commands with root-level privileges on the client machine during the domain join operation.\nThe risk is severe as it allows for full system compromise, lateral movement, and persistence establishment within the affected infrastructure.\nExploitation requires the victim client to initiate a domain join against a compromised or attacker-controlled Active Directory environment.",
  "technicalDetails": "The root cause of this vulnerability is the failure of the yast2-samba-client component to properly sanitize or validate data retrieved from an Active Directory directory tree before passing it to system-level command execution functions.\nDuring the process of joining an Active Directory domain, yast2-samba-client queries the directory for configuration metadata or object attributes. If these attributes contain shell metacharacters or command injection sequences, the underlying system interfaces may interpret these strings as executable commands rather than data.\nThe attack flow begins when an attacker, positioned as a rogue domain controller or a user with sufficient delegation to modify directory objects, injects malicious command payloads into fields that are subsequently processed by the yast2-samba-client module.\nWhen a legitimate administrator or automated system attempts to join a machine to the domain, yast2-samba-client retrieves the poisoned attributes. The application then constructs an OS command using this untrusted input.\nBecause the execution process runs with root privileges to perform sensitive system operations—such as modifying /etc/samba/smb.conf, updating /etc/nsswitch.conf, or invoking system utilities—the injected commands are executed with the same elevated permissions.\nThis vulnerability effectively bypasses security boundaries, allowing for arbitrary code execution (ACE) on the client side without needing prior access to the client machine, provided the attacker controls the AD environment being joined.\nThe payload behavior is limited only by the privileges of the executing process, which in this context is root. This allows an attacker to create new administrative users, exfiltrate local secrets, install persistent backdoors, or disable security auditing tools immediately upon the client's integration into the domain.\nThis flaw is specific to the handling of external inputs within the yast2-samba-client package in versions through 5.0.4. It demonstrates a breakdown in secure input handling where data integrity is assumed from the directory service rather than enforced at the application level through parameterized APIs or robust input sanitization routines."
}