peass-ng/PEASS-ng · error · ArgumentNullException

Value cannot be null. (Parameter 'array')

Error message

Value cannot be null. (Parameter 'array')

What it means

Null-argument guard in TaskFolderCollection.CopyTo (ICollection.CopyTo implementation): it fires when the destination array is null, before any folder enumeration happens, matching the standard .NET collection contract that a null destination array is rejected.

Source

Thrown at winPEAS/winPEASexe/winPEAS/TaskScheduler/TaskFolderCollection.cs:117

                for (var i = v2FolderList.Count; i > 0; i--)
                    if (string.Equals(item.Path, v2FolderList[i].Path, StringComparison.CurrentCultureIgnoreCase))
                        return true;
            }
            else
                return item.Path == "\\";
            return false;
        }

        /// <summary>Copies the elements of the ICollection to an Array, starting at a particular Array index.</summary>
        /// <param name="array">
        /// The one-dimensional Array that is the destination of the elements copied from <see cref="ICollection{T}"/>. The Array must have
        /// zero-based indexing.
        /// </param>
        /// <param name="arrayIndex">The zero-based index in array at which copying begins.</param>
        public void CopyTo(TaskFolder[] array, int arrayIndex)
        {
            if (arrayIndex < 0) throw new ArgumentOutOfRangeException(nameof(arrayIndex));
            if (array == null) throw new ArgumentNullException(nameof(array));
            if (v2FolderList != null)
            {
                if (arrayIndex + Count > array.Length)
                    throw new ArgumentException();
                foreach (var f in this)
                    array[arrayIndex++] = f;
            }
            else
            {
                if (arrayIndex + v1FolderList.Length > array.Length)
                    throw new ArgumentException();
                v1FolderList.CopyTo(array, arrayIndex);
            }
        }

        /// <summary>Releases all resources used by this class.</summary>
        public void Dispose()
        {

View on GitHub (pinned to 53fb989abc)

Solutions

1. Allocate the destination array before CopyTo (size >= Count)
2. Check for null before calling
3. Use foreach/ToArray instead of manual CopyTo

Example fix

// before
TaskFolder[] arr = null;
subFolders.CopyTo(arr, 0);
// after
var arr = new TaskFolder[subFolders.Count];
subFolders.CopyTo(arr, 0);

if (array == null) throw new ArgumentNullException(nameof(array));
if (array.Length < subFolders.Count) throw new ArgumentException("Array too small.");

try { subFolders.CopyTo(array, 0); }
catch (ArgumentNullException) { array = new TaskFolder[subFolders.Count]; subFolders.CopyTo(array, 0); }

When it happens

Trigger: Calling subFolders.CopyTo(null, 0), or passing an array variable that was never initialized.

Common situations: Copy/paste refactor where the array allocation was removed; conditional allocation skipped on some code path.

Related errors

• Specified argument was out of the range of valid values. (Pa
• Exception of type 'System.ArgumentException' was thrown.
• path
• Value cannot be null. Parameter name: path
• The array and none of the values passed as parameters may be

AI-assisted analysis of peass-ng/PEASS-ng@53fb989abc (2026-09-02). Data as JSON: /api/errors/105035ee4c90cbf7. Report an issue: GitHub.