diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index adac1b25d..654b16742 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,8 @@
+2002-06-03  Pierre Humblet <pierre.humblet@ieee.org>
+
+	* syscalls.cc (setegid32): Verify the correctness of the gid
+	of the group returned by getgrgid32.
+
 2002-06-03  Pierre Humblet <pierre.humblet@ieee.org>
 
 	* security.cc (lsa2wchar): Suppressed.
diff --git a/winsup/cygwin/syscalls.cc b/winsup/cygwin/syscalls.cc
index a936a21fd..54418c0a9 100644
--- a/winsup/cygwin/syscalls.cc
+++ b/winsup/cygwin/syscalls.cc
@@ -2175,7 +2175,8 @@ setegid32 (__gid32_t gid)
   cygsid gsid;
   HANDLE ptok;
 
-  if (!(gsid.getfromgr (getgrgid32 (gid))))
+  struct __group32 * gr = getgrgid32 (gid);
+  if (!gr || gr->gr_gid != gid || !gsid.getfromgr (gr))
     {
       set_errno (EINVAL);
       return -1;