Provide references for CVE-2021-31439.
Where can I find more information about CVE-2021-31439?
References are available at: https://www.zerodayinitiative.com/advisories/ZDI-21-492/, https://www.synology.com/zh-hk/security/advisory/Synology_SA_20_26, https://lists.debian.org/debian-lts-announce/2023/05/msg00018.html, https://www.debian.org/security/2023/dsa-5503, https://security.gentoo.org/glsa/202311-02.