DNS rebind bypasses IP check

Code reviewCode quality & reviewMid–Senior~20 min

Review this Java image-proxy that blocks internal IPs.

What a strong answer looks like

Separate real bugs from style. Rank issues by severity, point at the root cause rather than the symptom, and suggest a concrete fix, specific and kind.

0:00 of about 20 min

Mark a line and say what kind of problem it is.0 findings

1String fetch(String rawUrl) throws Exception {

2 URL url = new URL(rawUrl);

3 InetAddress addr = InetAddress.getByName(url.getHost());

4 if (addr.isSiteLocalAddress() || addr.isLoopbackAddress()) {

5 throw new SecurityException("blocked");

6 }

7 try (InputStream in = url.openStream()) {

8 return new String(in.readAllBytes());

9 }

10}

Which questions mattered is sealed until you submit. Telling you now would just be handing over the edge cases.