CVE-2023-47039 Red Hat CVE debrief

Who should care

Organizations running Siemens SINEC INS, particularly in industrial control system (ICS) environments. System administrators responsible for Windows-based Perl deployments. Security teams managing privilege escalation risks in multi-user Windows environments. Industrial operators following CISA ICS security guidance.

Technical summary

The vulnerability exists in how Perl for Windows locates the system shell (cmd.exe). When Perl needs to execute system commands, it searches for cmd.exe using the PATH environment variable. However, due to path search order implementation, Perl checks the current working directory before system directories. An attacker with limited write access can place a malicious cmd.exe in a directory with weak permissions (e.g., C:/ProgramData). When an administrator subsequently executes a Perl-based application from that directory, the malicious cmd.exe is loaded and executed with the administrator's privileges. This represents a classic DLL/preload-style attack adapted for shell execution on Windows systems. The attack requires local access and low privileges for initial placement, but enables high-impact arbitrary code execution when triggered by a privileged user.

Defensive priority

HIGH

Recommended defensive actions

• Update Siemens SINEC INS to V1.0 SP2 Update 3 or later version
• Apply vendor-provided security patches as referenced in Siemens advisory SSA-915275
• Restrict write permissions to directories commonly in execution paths such as C:/ProgramData
• Implement principle of least privilege for user accounts
• Monitor for unauthorized cmd.exe files in non-standard locations
• Apply defense-in-depth strategies for industrial control systems per CISA guidance

Evidence notes

CISA published advisory ICSA-24-319-08 on 2024-11-12 identifying this vulnerability in Siemens SINEC INS. The advisory references Siemens security advisory SSA-915275. The CVSS 3.1 vector AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H indicates a local attack vector with low attack complexity, requiring low privileges but no user interaction, with high impact on confidentiality, integrity, and availability.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.