Provide references for CVE-2021-3990.
Where can I find more information about CVE-2021-3990?
References are available at: https://huntr.dev/bounties/0680067d-56a7-4412-b06e-a267e850ae9f, https://github.com/star7th/showdoc/commit/a9886f26c08225e0adca75c67dfca3f7c42b87d0.