# UNDF: UNDF-2026-000000067
--- a/exposed-core/src/main/kotlin/org/jetbrains/exposed/v1/core/statements/api/IdentifierManagerApi.kt
+++ b/exposed-core/src/main/kotlin/org/jetbrains/exposed/v1/core/statements/api/IdentifierManagerApi.kt
@@ -35,6 +35,10 @@ abstract class IdentifierManagerApi {
     /** All keywords for the database, including [ANSI_SQL_2003_KEYWORDS] and database-specific keywords. */
     val keywords by lazy {
         ANSI_SQL_2003_KEYWORDS + VENDORS_KEYWORDS[currentDialect.name].orEmpty() + dbKeywords()
     }

+    // CWE-407 fix: pre-built lowercase HashSet for O(1) case-insensitive keyword lookup
+    private val keywordsLower: Set<String> by lazy {
+        keywords.mapTo(HashSet()) { it.lowercase() }
+    }
+
     /** The database-specific special characters that can be additionally used in unquoted identifiers. */
     protected abstract val extraNameCharacters: String
@@ -68,7 +73,7 @@ abstract class IdentifierManagerApi {
     private fun String.isAKeyword(): Boolean = checkedKeywordsCache.getOrPut(lowercase()) {
-        keywords.any { this.equals(it, true) }
+        this.lowercase() in keywordsLower
     }