fix(ip-validation): implement strict IPv4 format validation (#2429)

* fix(regex): correct IP validation to handle IPv4 edge cases and robust IPv6

* enhance(regex): improve IP extractor to prevent false positives and enforce IPv4 octet ranges

Tighten IPv4 pattern to enforce 0-255 per octet, rejecting invalid addresses like 256.256.256.256 and 999.999.999.999

Replace loose IPv6 matcher with comprehensive pattern covering full, compressed, link-local with zone IDs, and IPv4-embedded forms

Author: Pratyush2240

Specialized Areas/Regular Expressions/IP Address Validation/README.md

@@ -1,25 +1,24 @@
-The regex in the file getIP4OrIPV6address.js files validates for both ip address(ipv4) or ipv6 based on the input.
+This snippet extracts IPv4 and IPv6 addresses from free text. For single-value validation, see `validateIPInput.js` and `Validate IPv6 Address/script.js`.
 
-This regex cover the folloing IPv6 examples: 
-Full IPv6 addresses (e.g., 2001:0db8:85a3:0000:0000:8a2e:0370:7334).
-Shorthand versions (e.g., fe80::1, where :: represents omitted zeros).
-IPv6 with embedded IPv4 addresses (e.g., ::ffff:192.168.1.1).
-And also includes following IPv4 addresses.
-Following are the valid IP address examples:
+The regex in `getIP4OrIPV6address.js` finds both IPv4 and IPv6 addresses within arbitrary text content.
 
-192.168.1.1
+IPv6 coverage includes:
+- Full addresses like `2001:0db8:85a3:0000:0000:8a2e:0370:7334`
+- Compressed forms like `fe80::1` (`::` for omitted zeros)
+- IPv4-embedded forms like `::ffff:192.168.1.1`
 
-127.0.0.1
+IPv4 validation now strictly enforces each octet to be in the range 0–255.
 
-0.0.0.0
+Valid IPv4 examples:
 
-255.255.255.255
+- 192.168.1.1
+- 127.0.0.1
+- 0.0.0.0
+- 255.255.255.255
+- 1.2.3.4
 
-256.256.256.256
-
-999.999.999.999
-
-1.2.3
-
-1.2.3.4
+Invalid IPv4 examples (correctly rejected by the regex):
 
+- 256.256.256.256
+- 999.999.999.999
+- 1.2.3

Specialized Areas/Regular Expressions/IP Address Validation/getIP4OrIPV6address.js

@@ -1,5 +1,26 @@
+// Extracts IPv4 and IPv6 addresses from arbitrary text content
+// For single-value validation, use validateIPInput.js or Validate IPv6 Address/script.js
 extractIPAddresses: function(text) {
-        var ipRegex = /\b((\d{1,3}\.){3}\d{1,3})\b|\b([a-fA-F0-9:]+:+[a-fA-F0-9:]+)\b/g;
-		var matches = text.match(ipRegex);
+        var ipv4 = "(?:25[0-5]|2[0-4]\\d|1?\\d?\\d)(?:\\.(?:25[0-5]|2[0-4]\\d|1?\\d?\\d)){3}";
+        var ipv6 = "("+
+            "(?:[A-Fa-f0-9]{1,4}:){7}[A-Fa-f0-9]{1,4}|"+
+            "(?:[A-Fa-f0-9]{1,4}:){1,7}:|"+
+            "(?:[A-Fa-f0-9]{1,4}:){1,6}:[A-Fa-f0-9]{1,4}|"+
+            "(?:[A-Fa-f0-9]{1,4}:){1,5}(?::[A-Fa-f0-9]{1,4}){1,2}|"+
+            "(?:[A-Fa-f0-9]{1,4}:){1,4}(?::[A-Fa-f0-9]{1,4}){1,3}|"+
+            "(?:[A-Fa-f0-9]{1,4}:){1,3}(?::[A-Fa-f0-9]{1,4}){1,4}|"+
+            "(?:[A-Fa-f0-9]{1,4}:){1,2}(?::[A-Fa-f0-9]{1,4}){1,5}|"+
+            "[A-Fa-f0-9]{1,4}:(?:(?::[A-Fa-f0-9]{1,4}){1,6})|"+
+            ":(?:(?::[A-Fa-f0-9]{1,4}){1,7}|:)|"+
+            "fe80:(?::[A-Fa-f0-9]{0,4}){0,4}%[0-9A-Za-z]{1,}|"+
+            "::(?:ffff(?::0{1,4}){0,1}:){0,1}(?:"+
+                "(?:25[0-5]|2[0-4]\\d|1?\\d?\\d)(?:\\.(?:25[0-5]|2[0-4]\\d|1?\\d?\\d)){3}"+
+            ")|"+
+            "(?:[A-Fa-f0-9]{1,4}:){1,4}:(?:"+
+                "(?:25[0-5]|2[0-4]\\d|1?\\d?\\d)(?:\\.(?:25[0-5]|2[0-4]\\d|1?\\d?\\d)){3}"+
+            ")"+
+        ")";
+        var ipRegex = new RegExp("\\b(?:" + ipv4 + "|" + ipv6 + ")\\b","g");
+        var matches = text.match(ipRegex);
         return matches;
     },