diff --git a/monkey/common/credentials/validators.py b/monkey/common/credentials/validators.py
new file mode 100644
index 000000000..3d1b74650
--- /dev/null
+++ b/monkey/common/credentials/validators.py
@@ -0,0 +1,6 @@
+import re
+
+from marshmallow import validate
+
+_ntlm_hash_regex = re.compile(r"^[a-fA-F0-9]{32}$")
+ntlm_hash_validator = validate.Regexp(regex=_ntlm_hash_regex)