1 files changed, 6 insertions, 5 deletions

diff --git a/src/firejail/main.c b/src/firejail/main.c
index e02554c5e..a9af46b6f 100644
--- a/src/firejail/main.c
+++ b/src/firejail/main.c
@@ -866,11 +866,12 @@ static void run_builder(int argc, char **argv) {
         (void) argc;
 
         // drop privileges
-        EUID_ROOT();
-        if (setgid(getgid()) < 0)
-                errExit("setgid/getgid");
-        if (setuid(getuid()) < 0)
-                errExit("setuid/getuid");
+        gid_t gid = getgid();
+        uid_t uid = getuid();
+        if (setresgid(gid, gid, gid) != 0)
+                errExit("setresgid");
+        if (setresuid(uid, uid, uid) != 0)
+                errExit("setresuid");
 
         assert(getenv("LD_PRELOAD") == NULL);
         umask(orig_umask);