diff --git a/Controllers/CookieProxyController.cs b/Controllers/CookieProxyController.cs
index 3779327..369c30e 100644
--- a/Controllers/CookieProxyController.cs
+++ b/Controllers/CookieProxyController.cs
@@ -14,17 +14,19 @@ public class CookieProxyController : Controller {
 		// Check if we are on the correct domain
 		if (Request.Host.Host != Vars.AuthProxySubdomain + "." + Vars.UpstreamPrimaryDomain)
 			return StatusCode(StatusCodes.Status421MisdirectedRequest);
-		
+
 		if (!Request.Cookies.ContainsKey("authelia_session")
 		 || string.IsNullOrWhiteSpace(dstDomain)
 		 || !Vars.PermittedDomains.Contains(dstDomain)
-		 || string.IsNullOrWhiteSpace(tgt)) {
+		 || string.IsNullOrWhiteSpace(tgt)
+		 || !new Uri(tgt).Host.EndsWith(dstDomain)) {
 			return BadRequest("Bad request.");
 		}
 
-		var targetUrl =
-			$"https://{Vars.AuthProxySubdomain}.{dstDomain}/api/cookieproxy_stage_two?dstDomain={HttpUtility.UrlEncode(dstDomain)}&tgt={HttpUtility.UrlEncode(tgt)}";
-		return Content($"Redirecting to cookie proxy (stage two) on the destination domain... <form method=\"POST\" action=\"{targetUrl}\"> <input type=\"hidden\" name=\"cookie\" value=\"{HttpUtility.HtmlEncode(Request.Cookies["authelia_session"])}\"><button type=\"submit\">Click here</button> if you are not redirected automatically</form><script>document.querySelector(\"form\").submit();</script>", "text/html");
+		var targetUrl = $"https://{Vars.AuthProxySubdomain}.{dstDomain}/api/cookieproxy_stage_two?dstDomain={HttpUtility.UrlEncode(dstDomain)}&tgt={HttpUtility.UrlEncode(tgt)}";
+		return
+			Content($"Redirecting to cookie proxy (stage two) on the destination domain... <form method=\"POST\" action=\"{targetUrl}\"> <input type=\"hidden\" name=\"cookie\" value=\"{HttpUtility.HtmlEncode(Request.Cookies["authelia_session"])}\"><button type=\"submit\">Click here</button> if you are not redirected automatically</form><script>document.querySelector(\"form\").submit();</script>",
+				    "text/html");
 	}
 
 	[HttpPost]
@@ -35,7 +37,11 @@ public class CookieProxyController : Controller {
 		if (!Request.Host.Host.StartsWith(Vars.AuthProxySubdomain + ".") || !Vars.PermittedDomains.Any(p => Request.Host.Host.EndsWith("." + p)))
 			return StatusCode(StatusCodes.Status421MisdirectedRequest);
 
-		if (string.IsNullOrWhiteSpace(dstDomain) || !Vars.PermittedDomains.Contains(dstDomain) || string.IsNullOrWhiteSpace(cookie) || string.IsNullOrWhiteSpace(tgt)) {
+		if (string.IsNullOrWhiteSpace(dstDomain)
+		 || !Vars.PermittedDomains.Contains(dstDomain)
+		 || string.IsNullOrWhiteSpace(cookie)
+		 || string.IsNullOrWhiteSpace(tgt)
+		 || !new Uri(tgt).Host.EndsWith(dstDomain)) {
 			return BadRequest("Bad request.");
 		}
 
diff --git a/Controllers/RedirectController.cs b/Controllers/RedirectController.cs
index e41e620..4a6652e 100644
--- a/Controllers/RedirectController.cs
+++ b/Controllers/RedirectController.cs
@@ -14,7 +14,7 @@ public class RedirectController : Controller {
 			return StatusCode(StatusCodes.Status421MisdirectedRequest);
 		}
 
-		if (string.IsNullOrWhiteSpace(dstDomain) || !Vars.PermittedDomains.Contains(dstDomain) || string.IsNullOrWhiteSpace(tgt)) {
+		if (string.IsNullOrWhiteSpace(dstDomain) || !Vars.PermittedDomains.Contains(dstDomain) || string.IsNullOrWhiteSpace(tgt) || !new Uri(tgt).Host.EndsWith(dstDomain)) {
 			Response.StatusCode = StatusCodes.Status421MisdirectedRequest;
 			return BadRequest("Bad request.");
 		}