CVE-2026-30309 Overview
CVE-2026-30309 is a command injection vulnerability in Tokfinity InfCode's terminal auto-execution module. The blacklist-based command filtering mechanism fails to block native Windows PowerShell binaries such as powershell. The matching algorithm performs only static string comparison and cannot parse shell syntax constructs like string concatenation, variable assignment, or double-quote interpolation. Attackers can craft a file containing malicious instructions that, when imported and viewed in the IDE, cause the InfCode Agent to execute PowerShell commands without user confirmation. The flaw is classified under CWE-78 (OS Command Injection).
Critical Impact
Successful exploitation leads to arbitrary command execution on the developer's workstation and potential exposure of sensitive local data.
Affected Products
- Tokfinity InfCode (all versions matching cpe:2.3:a:tokfinity:infcode:*)
- InfCode terminal auto-execution module
- InfCode IDE Agent component
Discovery Timeline
- 2026-03-31 - CVE-2026-30309 published to NVD
- 2026-04-14 - Last updated in NVD database
Technical Details for CVE-2026-30309
Vulnerability Analysis
The InfCode Agent ships with a terminal auto-execution feature that runs shell commands proposed by an LLM tool-calling workflow. To restrict dangerous operations, the Agent applies a predefined blacklist before dispatching commands. The blacklist omits common Windows-native interpreters, including powershell and powershell.exe. Any command routed through PowerShell therefore reaches the host shell without restriction.
The filter compares command tokens as literal strings. It does not tokenize or normalize input before matching. Shell features such as variable substitution, concatenated string literals, and quoted interpolation allow an attacker to reassemble blocked tokens at runtime. The blacklist sees benign fragments while the shell receives a fully reconstructed dangerous command.
Exploitation requires no user confirmation. When a developer opens a malicious file in the IDE, the Agent reads embedded instructions and invokes the terminal module directly. The local attack vector and required user interaction are reflected in the CVSS metrics.
Root Cause
The root cause is reliance on a static deny-list for security decisions on untrusted input. The list does not enumerate the full set of Windows command interpreters. The matcher also lacks semantic awareness of shell grammar, so syntactically obfuscated commands evade detection.
Attack Vector
An attacker prepares a project file or document containing crafted LLM instructions. The victim imports the file into InfCode and opens it. The Agent parses the embedded tool-call instructions and issues a PowerShell command built with concatenation or variable interpolation. The terminal module executes the reconstructed command in the user's security context, enabling code execution or data exfiltration.
The vulnerability mechanism is described in the GitHub Issue Discussion. No public proof-of-concept exploit is currently available.
Detection Methods for CVE-2026-30309
Indicators of Compromise
- Unexpected powershell.exe or pwsh.exe child processes spawned by the InfCode IDE process or its Agent helper.
- PowerShell command lines containing variable assignments or concatenated strings that resolve to download, encode, or Invoke-Expression operations.
- Outbound network connections from PowerShell processes initiated shortly after a file import event in InfCode.
Detection Strategies
- Hunt for process trees where the InfCode Agent is the parent of powershell.exe, cmd.exe, or wscript.exe.
- Inspect PowerShell ScriptBlock logs (Event ID 4104) for obfuscated payloads originating from IDE-launched sessions.
- Correlate file-open telemetry in developer workstations with terminal command execution within a short time window.
Monitoring Recommendations
- Enable PowerShell module logging, ScriptBlock logging, and transcription on developer endpoints.
- Forward Sysmon process creation events with parent-process context to a central SIEM for analysis.
- Track InfCode version inventory and flag hosts running unpatched releases.
How to Mitigate CVE-2026-30309
Immediate Actions Required
- Disable the InfCode terminal auto-execution feature until a vendor patch is applied.
- Prohibit importing or opening untrusted project files, notebooks, or shared workspaces in InfCode.
- Restrict PowerShell execution policy on developer workstations and apply AppLocker or WDAC rules to limit interpreter use.
- Require explicit user confirmation for any Agent-initiated shell command via available configuration settings.
Patch Information
No vendor advisory or fixed version is listed in the NVD record at the time of publication. Monitor the Tokfinity InfCode product page and the upstream issue tracker for updates. Apply the vendor-supplied patch as soon as it becomes available.
Workarounds
- Replace blacklist filtering with an allow-list of explicitly approved commands where the configuration permits.
- Run InfCode under a low-privilege account with no access to sensitive credentials or source repositories.
- Block egress traffic from developer endpoints to untrusted destinations to limit exfiltration impact.
# Configuration example: restrict PowerShell via AppLocker on developer hosts
# Create a default-deny rule for PowerShell, allowing only signed admin scripts
New-AppLockerPolicy -RuleType Publisher,Hash -User Everyone `
-RuleNamePrefix "InfCode-Mitigation" `
-XMLPolicy "C:\Policies\block-powershell.xml"
Set-AppLockerPolicy -XMLPolicy "C:\Policies\block-powershell.xml" -Merge
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
