diff --git a/internal/server/const.go b/internal/server/const.go
index 098a5bea..ae815cd4 100644
--- a/internal/server/const.go
+++ b/internal/server/const.go
@@ -59,7 +59,6 @@ X_AUTHELIA_HEALTHCHECK_PATH=%s
 `
 
 const (
-	cspDefaultTemplate    = "default-src 'self'; object-src 'none'; style-src 'self' 'nonce-%s'"
-	cspDefaultDevTemplate = "default-src 'self' 'unsafe-eval'; object-src 'none'; style-src 'self' 'nonce-%s'"
-	cspNoncePlaceholder   = "${NONCE}"
+	cspDefaultTemplate  = "default-src 'self'%s; frame-src 'none'; object-src 'none'; style-src 'self' 'nonce-%s'; frame-ancestors 'none'; base-uri 'self'"
+	cspNoncePlaceholder = "${NONCE}"
 )
diff --git a/internal/server/template.go b/internal/server/template.go
index 31b81250..9c5bb523 100644
--- a/internal/server/template.go
+++ b/internal/server/template.go
@@ -76,9 +76,9 @@ func ServeTemplatedFile(publicDir, file, assetPath, duoSelfEnrollment, rememberM
 		case ctx.Configuration.Server.Headers.CSPTemplate != "":
 			ctx.Response.Header.Add("Content-Security-Policy", strings.ReplaceAll(ctx.Configuration.Server.Headers.CSPTemplate, cspNoncePlaceholder, nonce))
 		case os.Getenv("ENVIRONMENT") == dev:
-			ctx.Response.Header.Add("Content-Security-Policy", fmt.Sprintf(cspDefaultDevTemplate, nonce))
+			ctx.Response.Header.Add("Content-Security-Policy", fmt.Sprintf(cspDefaultTemplate, " 'unsafe-eval'", nonce))
 		default:
-			ctx.Response.Header.Add("Content-Security-Policy", fmt.Sprintf(cspDefaultTemplate, nonce))
+			ctx.Response.Header.Add("Content-Security-Policy", fmt.Sprintf(cspDefaultTemplate, "", nonce))
 		}
 
 		err := tmpl.Execute(ctx.Response.BodyWriter(), struct{ Base, BaseURL, CSPNonce, DuoSelfEnrollment, LogoOverride, RememberMe, ResetPassword, ResetPasswordCustomURL, Session, Theme string }{Base: base, BaseURL: baseURL, CSPNonce: nonce, DuoSelfEnrollment: duoSelfEnrollment, LogoOverride: logoOverride, RememberMe: rememberMe, ResetPassword: resetPassword, ResetPasswordCustomURL: resetPasswordCustomURL, Session: session, Theme: theme})