feat(checksum): odd number of hexa characters is wrong formatting

Author: RenjiSann

src/uucore/src/lib/features/checksum.rs

@@ -469,7 +469,13 @@ fn get_expected_digest_as_hexa_string(caps: &Captures, chosen_regex: &Regex) ->
     if chosen_regex.as_str() == ALGO_BASED_REGEX_BASE64 {
         BASE64.decode(ck).map(hex::encode).ok()
     } else {
-        Some(str::from_utf8(ck).unwrap().to_string())
+        if ck.len() % 2 != 0 {
+            // If the length of the digest is not a multiple of 2, then it
+            // must be improperly formatted (1 hexa digit is 2 characteres)
+            None
+        } else {
+            Some(str::from_utf8(ck).unwrap().to_string())
+        }
     }
 }