MATCHED_VARS_NAMES
Description: All matched variable names
Syntax: MATCHED_VARS_NAMES
MATCHED_VARS_NAMES is a collection variable containing the names of all variables that matched successfully in the current rule. Unlike MATCHED_VAR_NAME, when a rule matches multiple variables, this variable contains all matched variable names.
Example:
# Log all matched variable names
SecRule ARGS|REQUEST_HEADERS "@detectSQLi" \
"id:1066,phase:2,deny,msg:'SQL injection in: %{MATCHED_VARS_NAMES}'"