1 files changed, 7 insertions, 0 deletions

diff --git a/src/firejail/main.c b/src/firejail/main.c
index 53300fe2d..b8ed29ece 100644
--- a/src/firejail/main.c
+++ b/src/firejail/main.c
@@ -2397,6 +2397,13 @@ int main(int argc, char **argv, char **envp) {
                                         fprintf(stderr, "Error: invalid MAC address\n");
                                         exit(1);
                                 }
+
+                                // check multicast address
+                                if (br->macsandbox[0] & 1) {
+                                        fprintf(stderr, "Error: invalid MAC address (multicast)\n");
+                                        exit(1);
+                                }
+
                         }
                         else
                                 exit_err_feature("networking");