diff --git a/towncrier/newsfragments/2693.bugfix b/towncrier/newsfragments/2693.bugfix
new file mode 100644
index 00000000..f299a25e
--- /dev/null
+++ b/towncrier/newsfragments/2693.bugfix
@@ -0,0 +1 @@
+Tweak the snuffleupagus rules to make roundcube's caldav work
diff --git a/webmails/snuffleupagus.rules b/webmails/snuffleupagus.rules
index cec99c29..8dde7cee 100644
--- a/webmails/snuffleupagus.rules
+++ b/webmails/snuffleupagus.rules
@@ -84,7 +84,9 @@ sp.disable_function.function("ini_set").param("option").value("include_path").dr
 sp.disable_function.function("ini_set").param("option").value("open_basedir").drop();
 
 # Detect some backdoors via environment recon
-sp.disable_function.function("ini_get").filename("/var/www/roundcube/vendor/guzzlehttp/guzzle/src/functions.php").param("option").value("allow_url_fopen").allow();
+sp.disable_function.function("ini_get").filename_r("^/var/www/snappymail/snappymail/v/[0-9]+\.[0-9]+\.[0-9]+/app/libraries/RainLoop/Utils\.php$").param("option").value("open_basedir").allow();
+sp.disable_function.function("ini_get").filename("/var/www/roundcube/vendor/guzzlehttp/guzzle/src/Utils.php").param("option").value("allow_url_fopen").allow();
+sp.disable_function.function("ini_get").filename("/var/www/roundcube/plugins/managesieve/lib/Roundcube/rcube_sieve_engine.php").param("option").value_r("suhosin").allow();
 sp.disable_function.function("ini_get").param("option").value("allow_url_fopen").drop();
 sp.disable_function.function("ini_get").param("option").value("open_basedir").drop();
 sp.disable_function.function("ini_get").param("option").value_r("suhosin").drop();