Code RoomJWT kid header injection

HardPrep Room Coding #2058

JWT kid header injection

Code reviewSecuritySenior–Staff~24 min

Review this Node JWT verifier that resolves the signing key from the token header.

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 24 min

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

1const jwt = require('jsonwebtoken');

2const fs = require('fs');

3

4function verify(token) {

5 const { header } = jwt.decode(token, { complete: true });

6 const keyPath = `/etc/keys/${header.kid}.pem`;

7 const key = fs.readFileSync(keyPath, 'utf8');

8 return jwt.verify(token, key, { algorithms: ['RS256'] });

9}

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