fix(validator): add null byte detection and fix tests

- Add null byte regex pattern to Validator class
- Check for null bytes in argument validation before spawn
- Fix test error message pattern case sensitivity
- Ensure consistent synchronous validation for null bytes

Author: NeaByteLab

src/utils/validator.ts

@@ -6,6 +6,8 @@ import type * as Types from '@interfaces/index.ts'
  * @description Security checks for execution.
  */
 export class Validator {
+  /** Pattern for null byte detection */
+  private static readonly nullByteRegex: RegExp = /\x00/
   /** Pattern for path traversal detection */
   private static readonly pathTraversalRegex: RegExp = /\.\.(?:\/|\\)|\.\.$/
   /** Pattern for shell metacharacters */
@@ -73,6 +75,12 @@ export class Validator {
     }
     for (let i = 0; i < args.length; i++) {
       const currentArg = args[i]!
+      if (this.nullByteRegex.test(currentArg)) {
+        return {
+          valid: false,
+          error: `Null bytes detected in argument ${i}`
+        }
+      }
       if (this.shellMetacharRegex.test(currentArg)) {
         return {
           valid: false,

tests/security.test.ts

@@ -465,7 +465,11 @@ Deno.test(
       workspaces: ['/tmp'],
       commands: { allow: ['echo'], deny: [], maxArgs: 10, strictArgs: true, noShell: true }
     })
-    assertThrows(() => Terminal.execute('echo test\x00danger'), Error, 'null bytes')
+    assertThrows(
+      () => Terminal.execute('echo test\x00danger', { cwd: '/tmp', timeout: 5000 }),
+      Error,
+      'Null bytes'
+    )
     const result = await Terminal.execute('echo test\x01danger', { cwd: '/tmp', timeout: 5000 })
     assert(result.id.startsWith('term_'))
   }
@@ -491,7 +495,7 @@ Deno.test(
       workspaces: ['/tmp'],
       commands: { allow: ['cat'], deny: [], maxArgs: 10, strictArgs: true, noShell: true }
     })
-    assertThrows(() => Terminal.execute('cat /etc/passwd\x00.txt'), Error, 'null bytes')
+    assertThrows(() => Terminal.execute('cat /etc/passwd\x00.txt'), Error, 'Null bytes')
   }
 )