From 56055622f2a426b0404b4cf3149d4d9781844a34 Mon Sep 17 00:00:00 2001
From: mleem97 <52848568+mleem97@users.noreply.github.com>
Date: Sat, 15 Aug 2026 23:53:11 +0000
Subject: [PATCH] Fix path traversal vulnerability in SetPortrait

Wrapped the file loading loop in a conditional block to validate `employeeId`
against directory traversal characters and invalid file name characters.
The fallback UI logic remains reachable.
---
 src/API/CustomEmployeeManager.cs | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/src/API/CustomEmployeeManager.cs b/src/API/CustomEmployeeManager.cs
index 9b4512b6..a0c115d6 100644
--- a/src/API/CustomEmployeeManager.cs
+++ b/src/API/CustomEmployeeManager.cs
@@ -891,10 +891,19 @@ private static void SetPortrait(Transform card, string employeeId)
 
             string assetsDir = Path.Combine(MelonEnvironment.UserDataDirectory, "ModAssets");
             string? imagePath = null;
-            foreach (var ext in new[] { ".jpg", ".png" })
+
+            // [Security] Prevent path traversal when loading portraits
+            if (employeeId.IndexOfAny(Path.GetInvalidFileNameChars()) < 0 && !employeeId.Contains(".."))
+            {
+                foreach (var ext in new[] { ".jpg", ".png" })
+                {
+                    string candidate = Path.Combine(assetsDir, employeeId + ext);
+                    if (File.Exists(candidate)) { imagePath = candidate; break; }
+                }
+            }
+            else
             {
-                string candidate = Path.Combine(assetsDir, employeeId + ext);
-                if (File.Exists(candidate)) { imagePath = candidate; break; }
+                CrashLog.Log($"[Security] CustomEmployee: Rejecting portrait load for invalid id={employeeId}");
             }
 
             if (imagePath != null)