diff --git a/bin/sh/var.c b/bin/sh/var.c
index d5b252230cb0..b3bc6f7fdf8f 100644
--- a/bin/sh/var.c
+++ b/bin/sh/var.c
@@ -612,6 +612,12 @@ showvarscmd(int argc __unused, char **argv __unused)
 
 	qsort(vars, n, sizeof(*vars), var_compare);
 	for (i = 0; i < n; i++) {
+		/*
+		 * Skip improper variable names so the output remains usable as
+		 * shell input.
+		 */
+		if (!isassignment(vars[i]))
+			continue;
 		s = strchr(vars[i], '=');
 		s++;
 		outbin(vars[i], s - vars[i], out1);
@@ -683,6 +689,13 @@ exportcmd(int argc, char **argv)
 			for (vp = *vpp ; vp ; vp = vp->next) {
 				if (vp->flags & flag) {
 					if (values) {
+						/*
+						 * Skip improper variable names
+						 * so the output remains usable
+						 * as shell input.
+						 */
+						if (!isassignment(vp->text))
+							continue;
 						out1str(cmdname);
 						out1c(' ');
 					}
diff --git a/tools/regression/bin/sh/builtins/export1.0 b/tools/regression/bin/sh/builtins/export1.0
new file mode 100644
index 000000000000..7b08c9de4349
--- /dev/null
+++ b/tools/regression/bin/sh/builtins/export1.0
@@ -0,0 +1,3 @@
+# $FreeBSD$
+
+env @badness=1 ${SH} -c 'v=`export -p`; eval "$v"'
diff --git a/tools/regression/bin/sh/builtins/set2.0 b/tools/regression/bin/sh/builtins/set2.0
new file mode 100644
index 000000000000..ad13eab0a7b8
--- /dev/null
+++ b/tools/regression/bin/sh/builtins/set2.0
@@ -0,0 +1,3 @@
+# $FreeBSD$
+
+! env @badness=1 ${SH} -c 'v=`set`; eval "$v"' 2>&1 | grep @badness