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JS: promote the js/jwt-missing-verification query out of experimental #7740

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Original file line number Diff line number Diff line change
@@ -0,0 +1,42 @@
<!DOCTYPE qhelp PUBLIC "-//Semmle//qhelp//EN" "qhelp.dtd"> <qhelp>

<overview>
<p>
Applications decoding JSON Web Tokens (JWT) may be misconfigured due to the <code>None</code> algorithm.
</p>
<p>
The <code>None</code> algorithm is selected by calling the <code>verify()</code> function with a falsy value
instead of a cryptographic secret or key. The <code>None</code> algorithm disables the integrity enforcement of
a JWT payload and may allow a malicious actor to make unintended changes to a JWT payload leading
to critical security issues like privilege escalation.
</p>

</overview>

<recommendation>
<p>
Calls to <code>verify()</code> functions should use a cryptographic secret or key to decode JWT payloads.
</p>
</recommendation>

<example>
<p>
In the example below, <code>false</code> is used to disable the integrity enforcement of a JWT payload.
This may allow a malicious actor to make changes to a JWT payload.
</p>

<sample src="examples/missing-key-verification-bad.js" />

<p>
The following code fixes the problem by using a cryptographic secret or key to decode JWT payloads.
</p>

<sample src="examples/missing-key-verification-good.js" />

</example>

<references>
<li>Auth0 Blog: <a href="https://auth0.com/blog/critical-vulnerabilities-in-json-web-token-libraries/#Meet-the--None--Algorithm">Meet the "None" Algorithm</a>.</li>

</references>
</qhelp>
Original file line number Diff line number Diff line change
Expand Up @@ -10,12 +10,11 @@
*/

import javascript
import DataFlow
import semmle.javascript.RestrictedLocations

from CallNode call
from DataFlow::CallNode call
where
call = moduleMember("jsonwebtoken", "verify").getACall() and
unique(boolean b | b = call.getArgument(1).analyze().getABooleanValue()) = false
select call.asExpr().(FirstLineOf),
"does not verify the JWT payload with a cryptographic secret or public key."
call = DataFlow::moduleMember("jsonwebtoken", "verify").getACall() and
call.getArgument(1).analyze().getTheBooleanValue() = false
select call.getArgument(1),
"This argument disables the integrity enforcement of the token verification."
Original file line number Diff line number Diff line change
@@ -0,0 +1,6 @@
const jwt = require("jsonwebtoken");

const secret = "my-secret-key";

var token = jwt.sign({ foo: 'bar' }, secret, { algorithm: "none" })
jwt.verify(token, false, { algorithms: ["HS256", "none"] })
Original file line number Diff line number Diff line change
@@ -0,0 +1,7 @@

const jwt = require("jsonwebtoken");

const secret = "my-secret-key";

var token = jwt.sign({ foo: 'bar' }, secret, { algorithm: "HS256" })
jwt.verify(token, secret, { algorithms: ["HS256", "none"] })
Original file line number Diff line number Diff line change
@@ -0,0 +1,4 @@
---
category: newQuery
---
* A new query `js/jwt-missing-verification` has been added. The query detects applications that don't verify JWT tokens.

This file was deleted.

Original file line number Diff line number Diff line change
@@ -0,0 +1,3 @@
| bad-jwt.js:10:19:10:20 | "" | This argument disables the integrity enforcement of the token verification. |
| bad-jwt.js:11:19:11:27 | undefined | This argument disables the integrity enforcement of the token verification. |
| bad-jwt.js:12:19:12:23 | false | This argument disables the integrity enforcement of the token verification. |
Original file line number Diff line number Diff line change
@@ -0,0 +1 @@
Security/CWE-347/MissingJWTKeyVerification.ql
Original file line number Diff line number Diff line change
@@ -1,11 +1,12 @@
const jwt = require("jsonwebtoken");

const secret = "buybtc";
// #1
var token = jwt.sign({ foo: 'bar' }, secret, { algorithm: "HS256" }) // alg:HS256
jwt.verify(token, secret, { algorithms: ["HS256", "none"] }) // pass
// #2
var token = jwt.sign({ foo: 'bar' }, secret, { algorithm: "none" }) // alg:none (unsafe)
jwt.verify(token, "", { algorithms: ["HS256", "none"] }) // detected
jwt.verify(token, undefined, { algorithms: ["HS256", "none"] }) // detected
jwt.verify(token, false, { algorithms: ["HS256", "none"] }) // detected
const secret = "my-secret-key";

var token = jwt.sign({ foo: 'bar' }, secret, { algorithm: "HS256" })
jwt.verify(token, secret, { algorithms: ["HS256", "none"] }) // OK


var token = jwt.sign({ foo: 'bar' }, secret, { algorithm: "none" })
jwt.verify(token, "", { algorithms: ["HS256", "none"] }) // NOT OK
jwt.verify(token, undefined, { algorithms: ["HS256", "none"] }) // NOT OK
jwt.verify(token, false, { algorithms: ["HS256", "none"] }) // NOT OK