sqlmapproject/sqlmap · error · SqlmapValueException

tamper function '%s' returns invalid payload type ('%s')

Error message

tamper function '%s' returns invalid payload type ('%s')

What it means

Error "tamper function '%s' returns invalid payload type ('%s')" thrown in sqlmapproject/sqlmap.

Source

Thrown at lib/request/connect.py:1230

        if payload:
            delimiter = conf.paramDel or (DEFAULT_GET_POST_DELIMITER if place != PLACE.COOKIE else DEFAULT_COOKIE_DELIMITER)

            if not disableTampering and kb.tamperFunctions:
                for function in kb.tamperFunctions:
                    hints = {}

                    try:
                        payload = function(payload=payload, headers=auxHeaders, delimiter=delimiter, hints=hints)
                    except Exception as ex:
                        errMsg = "error occurred while running tamper "
                        errMsg += "function '%s' ('%s')" % (function.__name__, getSafeExString(ex))
                        raise SqlmapGenericException(errMsg)

                    if not isinstance(payload, six.string_types):
                        errMsg = "tamper function '%s' returns " % function.__name__
                        errMsg += "invalid payload type ('%s')" % type(payload)
                        raise SqlmapValueException(errMsg)

                value = agent.replacePayload(value, payload)

                if hints:
                    if HINT.APPEND in hints:
                        value = "%s%s%s" % (value, delimiter, hints[HINT.APPEND])

                    if HINT.PREPEND in hints:
                        if place == PLACE.URI:
                            match = re.search(r"\w+\s*=\s*%s" % PAYLOAD_DELIMITER, value) or re.search(r"[^?%s/]=\s*%s" % (re.escape(delimiter), PAYLOAD_DELIMITER), value)
                            if match:
                                value = value.replace(match.group(0), "%s%s%s" % (hints[HINT.PREPEND], delimiter, match.group(0)))
                        else:
                            value = "%s%s%s" % (hints[HINT.PREPEND], delimiter, value)

            logger.log(CUSTOM_LOGGING.PAYLOAD, safecharencode(payload.replace('\\', BOUNDARY_BACKSLASH_MARKER)).replace(BOUNDARY_BACKSLASH_MARKER, '\\'))

            if place == PLACE.CUSTOM_POST and kb.postHint:

View on GitHub (pinned to 0a35b20e39)

When it happens

Trigger: Thrown at lib/request/connect.py:1230 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of sqlmapproject/sqlmap@0a35b20e39 (2026-08-26). Data as JSON: /api/errors/61f88c3b172b4376. Report an issue: GitHub.