diff --git a/ChangeLog b/ChangeLog
index 7f5d748..02ea8bb 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -4,6 +4,7 @@
     mounted messages to stdout instead of stderr
     [devmon 1.1.1] use pmount ahead of udisks; test executables
     do not log read default config location
+    udevil.conf: iso9660 & udf add ro to prevent mount read-only warning
 0.2.3   2012-05-27:
     create /run/media/$USER on demand; add configure --with-setfacl-prog
     corrected Arch Linux udevil-git AUR package overwriting udevil.conf
diff --git a/etc/udevil.conf b/etc/udevil.conf
index 74a0916..e8b312f 100644
--- a/etc/udevil.conf
+++ b/etc/udevil.conf
@@ -213,6 +213,9 @@ forbidden_files =
 # WARNING:  OPTIONS PRESENT OR MISSING CAN CAUSE SERIOUS SECURITY PROBLEMS.
 default_options           = nosuid, noexec, nodev, noatime
 default_options_file      = nosuid, noexec, nodev, noatime, uid=$UID, gid=$GID, ro
+# mount iso9660 and udf with 'ro' to prevent mount read-only warning
+default_options_iso9660   = nosuid, noexec, nodev, noatime, uid=$UID, gid=$GID, ro
+default_options_udf       = nosuid, noexec, nodev, noatime, uid=$UID, gid=$GID, ro
 default_options_vfat      = nosuid, noexec, nodev, noatime, fmask=0022, dmask=0022, uid=$UID, gid=$GID
 default_options_msdos     = nosuid, noexec, nodev, noatime, fmask=0022, dmask=0022, uid=$UID, gid=$GID
 default_options_umsdos    = nosuid, noexec, nodev, noatime, fmask=0022, dmask=0022, uid=$UID, gid=$GID