[LEGIT] Fix - js/polynomial-redos

[liorn-test-app]

🔍 The problem

Polynomial regular expression used on uncontrolled data
See issue in Legit

🔒 Fix Details

Fixed a potential Regular Expression Denial of Service (ReDoS) vulnerability where user-controlled input (bankRouting from the request body) was passed directly to a regex test without length validation.

Added input validation that checks if bankRouting is a string and enforces a maximum length of 50 characters before the regex pattern is applied. This prevents attackers from submitting extremely large strings that could cause the regex engine to consume excessive CPU resources, even though the current regex pattern itself does not exhibit catastrophic backtracking.

This is a defense-in-depth measure that protects against resource exhaustion from oversized inputs while maintaining the existing validation logic for legitimate bank routing numbers.

--- a/app/routes/profile.js
+++ b/app/routes/profile.js
@@ -32,6 +32,20 @@
     this.handleProfileUpdate = (req, res, next) => {
 
         const {firstName, lastName, ssn, dob, address, bankAcc, bankRouting} = req.body;
+
+        // Validate bankRouting length to prevent ReDoS
+        if (typeof bankRouting !== 'string' || bankRouting.length > 50) {
+            return res.render("profile", {
+                updateError: "Bank Routing number format is invalid",
+                firstName,
+                lastName,
+                ssn,
+                dob,
+                address,
+                bankAcc,
+                bankRouting: ''
+            });
+        }
 
         // Fix for Section: ReDoS attack
         // The following regexPattern that is used to validate the bankRouting number is insecure and vulnerable to

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud