Do a range check on the resulting octal
diff --git a/libutil/unescape.c b/libutil/unescape.c
index 627c2a2..be18d1f 100644
--- a/libutil/unescape.c
+++ b/libutil/unescape.c
@@ -62,7 +62,7 @@
 				q += (s[m] - '0') * factor;
 				factor *= 8;
 			}
-			s[i] = q;
+			s[i] = (q > 255) 255 : q;
 		}
 
 		for (m = i + 1; m <= len - off; m++)