ruby/json: Ruby JSON: Denial of Service or Information Disclosure via format string injection

A flaw was found in Ruby JSON. This vulnerability, a format string injection, allows a remote attacker to cause a denial of service DoS or disclose sensitive information. The flaw occurs when processing specially crafted user-supplied documents with the allowduplicatekey: false parsing option...

CVE-2026-33210: Use of Externally-Controlled Format String

Ruby JSON is a JSON implementation for Ruby. From version 2.14.0 to before versions 2.15.2.1, 2.17.1.2, and 2.19.2, a format string injection vulnerability can lead to denial of service attacks or information disclosure, when the allowduplicatekey: false parsing option is used to parse user...

GHSA-3M6G-2423-7CP3 Ruby JSON has a format string injection vulnerability

Impact A format string injection vulnerability than that lead to denial of service attacks or information disclosure, when the allowduplicatekey: false parsing option is used to parse user supplied documents. This option isn't the default, if you didn't opt-in to use it, you are not impacted...