diff --git a/changelog b/changelog
index a9fd79b527b..637b8256cce 100644
--- a/changelog
+++ b/changelog
@@ -51,6 +51,8 @@ Version 1.13.0+dev:
    * Updated mainline campaigns and multiplayer scenarios to use [filter] status=
      instead of [filter] [filter_wml] [status]
    * Fixed a segfault in [move_units_fake]
+   * Fixed unbound memory read in the MP map selection screen that could lead
+     to a segmentation fault or other abnormal behavior (bug #23606).
 
 Version 1.13.0:
  * Security fixes:
diff --git a/src/game_initialization/create_engine.cpp b/src/game_initialization/create_engine.cpp
index d3f7e3858f5..52f5a50cbcb 100644
--- a/src/game_initialization/create_engine.cpp
+++ b/src/game_initialization/create_engine.cpp
@@ -148,7 +148,7 @@ surface scenario::create_image_surface(const SDL_Rect& image_rect)
 		return minimap_img_;
 	}
 
-	std::basic_string<unsigned char> current_hash = util::md5(map_->write());
+	std::string current_hash = util::encode_hash(util::md5(map_->write()));
 
 	if (minimap_img_.null() || (map_hash_ != current_hash)) { // If there's no minimap image, or the map hash doesn't match, regenerate the image cache.
 		minimap_img_ = image::getMinimap(image_rect.w, image_rect.h, *map_, 0);
diff --git a/src/game_initialization/create_engine.hpp b/src/game_initialization/create_engine.hpp
index a7c54249585..a87f5fe86c0 100644
--- a/src/game_initialization/create_engine.hpp
+++ b/src/game_initialization/create_engine.hpp
@@ -89,7 +89,7 @@ protected:
 	boost::scoped_ptr<gamemap> map_;
 
 	surface minimap_img_;
-	std::basic_string<unsigned char> map_hash_;
+	std::string map_hash_;
 
 private:
 	scenario(const scenario&);
diff --git a/src/hash.hpp b/src/hash.hpp
index 854ded0deab..e71e9f3086d 100644
--- a/src/hash.hpp
+++ b/src/hash.hpp
@@ -19,6 +19,13 @@
 
 namespace util {
 
+/**
+ * Returns the MD5 digest for the specified input.
+ *
+ * @note The returned value points to a fixed-size 16 bytes array representing
+ *       the raw MD5 value, not a null-terminated string. Use encode_hash if
+ *       you need the text representation instead.
+ */
 unsigned char* md5(const std::string& input);
 int get_iteration_count(const std::string& hash);
 std::string get_salt(const std::string& hash);