🔒 Unsanitized sandbox ID can lead to path traversal in request URL

[asmit25805]

🔒 Security · 🟠 High · Confidence: 94%

File: crates/forkd-cli/src/sandbox.rs
Location: delete_sandbox

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What's wrong

The sandbox ID is interpolated directly into the request URL without validation, allowing crafted IDs to target arbitrary endpoints. Problematic line: let url = format!("{}/v1/sandboxes/{}", daemon_url.trim_end_matches('/'), id);

Suggested fix

Validate or encode the id to ensure it contains only allowed characters (e.g., alphanumeric and hyphens) before constructing the URL:

if !id.chars().all(|c| c.is_ascii_alphanumeric() || c == '-') {
    anyhow::bail!("invalid sandbox id");
}
let url = format!("{}/v1/sandboxes/{}", daemon_url.trim_end_matches('/'), id);

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About this report

This finding was generated by an automated audit tool using Llama 3.3 70B + verification passes.
Only findings with ≥92% confidence that passed both LLM self-verification and line reference
verification are reported. False positives are still possible — please verify before acting.

[WaylandYang]

Thanks @asmit25805 — hardened in #262, again with a precise severity note.

delete_sandbox is the CLI talking to the operator's own daemon. Ids from --all/--tag come from the daemon's own list response (trusted); an explicit CLI id is user-controlled, and yes, ../snapshots would traverse the request path to another endpoint — but there's no privilege boundary crossed (you're hitting your own daemon, where you can already delete any sandbox you own), so this isn't really a path-traversal vuln in the security sense. The real win is a clear up-front "invalid sandbox id" error instead of a confusing 404 from a mangled path. #262 validates ids against [A-Za-z0-9_-] before the request, with unit tests. Appreciate the report.

[asmit25805]

Thanks for the detailed explanation and the swift fix in #262! Totally makes sense regarding the privilege boundary—catching the invalid ID early with a clean error is definitely a great improvement over a confusing 404. Appreciate you looking into it so quickly!