Provide references for CVE-2021-21239.
Where can I find more information about CVE-2021-21239?
References are available at: https://github.com/IdentityPython/pysaml2/security/advisories/GHSA-5p3x-r448-pc62, https://pypi.org/project/pysaml2, https://www.aleksey.com/pipermail/xmlsec/2013/009717.html, https://github.com/IdentityPython/pysaml2/releases/tag/v6.5.0, https://github.com/IdentityPython/pysaml2/commit/46578df0695269a16f1c94171f1429873f90ed99, https://lists.debian.org/debian-lts-announce/2021/02/msg00038.html.