In Apache APISIX before 2.13.0, when decoding JSON with duplicate keys, lua-cjson will choose the last occurred value as the result. By passing a JSON with a duplicate key, the attacker can bypass the body_schema validation in the request-validation plugin. For example, `{"string_payload":"bad","string_payload":"good"}` can be used to hide the "bad" input. Systems satisfy three conditions below are affected by this attack: 1. use body_schema validation in the request-validation plugin 2. upstream application uses a special JSON library that chooses the first occurred value, like jsoniter or gojay 3. upstream application does not validate the input anymore. The fix in APISIX is to re-encode the validated JSON input back into the request body at the side of APISIX. Improper Input Validation vulnerability in __COMPONENT__ of Apache APISIX allows an attacker to __IMPACT__. This issue affects Apache APISIX Apache APISIX version 2.12.1 and prior versions.
2022-03-28T07:15:06.730
2024-11-21T06:52:56.853
Modified
CVSSv3.1: 9.8 (CRITICAL)
AV:N/AC:M/Au:N/C:P/I:P/A:P
8.6
6.4