The vulnerability was explicitly linked to the _.words implementation in the lodash changelog entry for 4.17.11. The commit 5c08f18 shows the regex pattern in reHasUnicodeWord was modified from /[A-Z]{2,}[a-z]/ to /[A-Z]{2}[a-z]/ to prevent excessive backtracking. The added performance test in test.js specifically validates _.words' handling of 50k-character strings, confirming this was the attack vector. The CVE description's reference to 'date handler' appears to be an error, as all technical evidence points to the words function and unicode word detection logic.