1 files changed, 8 insertions, 0 deletions
diff --git a/src/mongo/db/matcher/expression_leaf.cpp b/src/mongo/db/matcher/expression_leaf.cpp
index ffe3a660a28..b1ca9d30342 100644
--- a/src/mongo/db/matcher/expression_leaf.cpp
+++ b/src/mongo/db/matcher/expression_leaf.cpp
@@ -46,6 +46,7 @@
 #include "mongo/db/query/collation/collator_interface.h"
 #include "mongo/stdx/memory.h"
 #include "mongo/util/mongoutils/str.h"
+#include "mongo/util/text.h"
 
 namespace mongo {
 
@@ -226,6 +227,13 @@ Status RegexMatchExpression::init(StringData path, StringData regex, StringData
 
     _regex = regex.toString();
     _flags = options.toString();
+
+    // isValidUTF8() checks for UTF-8 which does not map to a series of codepoints but does not
+    // check the validity of the code points themselves. These situations do not cause problems
+    // downstream so we do not do additional work to enforce that the code points are valid.
+    uassert(
+        5108300, "Regular expression is invalid UTF-8", isValidUTF8(_regex) && isValidUTF8(_flags));
+
     _re.reset(new pcrecpp::RE(_regex.c_str(), flags2options(_flags.c_str())));
 
     return setPath(path);