1 files changed, 7 insertions, 3 deletions
diff --git a/Jellyfin.Api/Controllers/PluginsController.cs b/Jellyfin.Api/Controllers/PluginsController.cs
index 0105ecf7a7..79b8b60cb7 100644
--- a/Jellyfin.Api/Controllers/PluginsController.cs
+++ b/Jellyfin.Api/Controllers/PluginsController.cs
@@ -6,6 +6,7 @@ using System.Linq;
 using System.Text.Json;
 using System.Threading.Tasks;
 using Jellyfin.Api.Attributes;
+using Jellyfin.Extensions;
 using Jellyfin.Extensions.Json;
 using MediaBrowser.Common.Api;
 using MediaBrowser.Common.Plugins;
@@ -226,10 +227,13 @@ public class PluginsController : BaseJellyfinApiController
             return NotFound();
         }
 
-        if (!string.IsNullOrEmpty(plugin.Manifest.ImagePath))
+        string? imagePath = plugin.Manifest.ImagePath;
+        if (!string.IsNullOrWhiteSpace(imagePath))
         {
-            var imagePath = Path.Combine(plugin.Path, plugin.Manifest.ImagePath);
-            if (!System.IO.File.Exists(imagePath))
+            var pluginPath = Path.TrimEndingDirectorySeparator(Path.GetFullPath(plugin.Path));
+            imagePath = Path.GetFullPath(imagePath, pluginPath);
+            // Require a separator after the plugin path so a sibling like "<pluginPath>-evil" can't pass.
+            if (imagePath.StartsWith(pluginPath + Path.DirectorySeparatorChar, StringComparison.OrdinalIgnoreCase) is false || System.IO.File.Exists(imagePath) is false)
             {
                 return NotFound();
             }