diff --git a/CHANGES b/CHANGES
index 850ca693f2..a87d486f22 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,4 +1,8 @@
 
+4.1.0-dev.318 | 2021-03-10 12:05:47 -0800
+
+  * Avoid searching a directory for dynamic plugins multiple times (Jon Siwek, Corelight)
+
 4.1.0-dev.316 | 2021-03-10 13:00:27 +0000
 
   * Fix potential mime type detection bug in IRC/FTP file_transferred event
diff --git a/VERSION b/VERSION
index 99ca693f60..a19cf70fbf 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-4.1.0-dev.316
+4.1.0-dev.318
diff --git a/src/plugin/Manager.cc b/src/plugin/Manager.cc
index d629455dae..da4ff5fe32 100644
--- a/src/plugin/Manager.cc
+++ b/src/plugin/Manager.cc
@@ -7,6 +7,8 @@
 #include <dlfcn.h>
 #include <errno.h>
 #include <sys/stat.h>
+#include <limits.h> // for PATH_MAX
+#include <cstdlib>
 #include <optional>
 #include <sstream>
 #include <fstream>
@@ -70,6 +72,19 @@ void Manager::SearchDynamicPlugins(const std::string& dir)
 		return;
 		}
 
+	char canon_path[PATH_MAX];
+	if ( ! realpath(dir.data(), canon_path) )
+		{
+		DBG_LOG(DBG_PLUGINS, "skip dynamic plugin search in %s, realpath failed: %s",
+		        dir.data(), strerror(errno));
+		return;
+		}
+
+	if ( searched_dirs.count(canon_path) )
+		return;
+
+	searched_dirs.emplace(canon_path);
+
 	// Check if it's a plugin dirctory.
 
 	const std::string magic = dir + "/__bro_plugin__";
diff --git a/src/plugin/Manager.h b/src/plugin/Manager.h
index c97a411304..6af81e7b96 100644
--- a/src/plugin/Manager.h
+++ b/src/plugin/Manager.h
@@ -416,6 +416,11 @@ private:
 	void MetaHookPre(HookType hook, const HookArgumentList& args) const;
 	void MetaHookPost(HookType hook, const HookArgumentList& args, const HookArgument& result) const;
 
+	// Directories that have already been searched for dynamic plugins.
+	// Used to prevent multiple searches of the same dirs (e.g. via symlinks).
+	// The paths stored in the set are made canonical via realpath().
+	std::set<std::string, std::less<>> searched_dirs;
+
 	// Plugins that were explicitly requested to be activated, but failed to
 	// load at first.
 	std::set<std::string> requested_plugins;