From 31808e83d5715f744ee3d74df7e3d0912c1038ea Mon Sep 17 00:00:00 2001
From: Shivam Kumar <shivamkingkumar5@gmail.com>
Date: Mon, 15 Jun 2026 14:04:25 +0530
Subject: [PATCH] Fix Uint8Array concat crash in Parse IPv4 header (#2409)

---
 src/core/operations/ParseIPv4Header.mjs    |  2 +-
 tests/operations/tests/ParseIPv4Header.mjs | 11 +++++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/src/core/operations/ParseIPv4Header.mjs b/src/core/operations/ParseIPv4Header.mjs
index a1ab93b3..65a8b63f 100644
--- a/src/core/operations/ParseIPv4Header.mjs
+++ b/src/core/operations/ParseIPv4Header.mjs
@@ -74,7 +74,7 @@ class ParseIPv4Header extends Operation {
             checksum = input[10] << 8 | input[11],
             srcIP = input[12] << 24 | input[13] << 16 | input[14] << 8 | input[15],
             dstIP = input[16] << 24 | input[17] << 16 | input[18] << 8 | input[19],
-            checksumHeader = input.slice(0, 10).concat([0, 0]).concat(input.slice(12, 20));
+            checksumHeader = [...input.slice(0, 10), 0, 0, ...input.slice(12, 20)];
         let version = (input[0] >>> 4) & 0x0f,
             options = [];
 
diff --git a/tests/operations/tests/ParseIPv4Header.mjs b/tests/operations/tests/ParseIPv4Header.mjs
index 47c2592a..ddebe3b9 100644
--- a/tests/operations/tests/ParseIPv4Header.mjs
+++ b/tests/operations/tests/ParseIPv4Header.mjs
@@ -19,5 +19,16 @@ TestRegister.addTests([
                 args: ["Hex", "Data (raw)"]
             }
         ]
+    },
+    {
+        name: "Parse IPv4 header: regression for Uint8Array.concat crash on truncated raw input",
+        input: "\x45\x00\x00\x14\x00\x00\x00\x00\x40\x06\x00\x00",
+        expectedOutput: "",
+        recipeConfig: [
+            {
+                op: "Parse IPv4 header",
+                args: ["Raw", "Data (raw)"]
+            }
+        ]
     }
 ]);