Tor before 0.4.3.6 has an out-of-bounds memory access that allows a remote denial-of-service (crash) attack against Tor instances built to use Mozilla Network Security Services (NSS), aka TROVE-2020-001.
https://trac.torproject.org/projects/tor/wiki/TROVE
https://gitlab.torproject.org/tpo/core/tor/-/issues/33119
https://blog.torproject.org/new-release-tor-03511-0428-0436-security-fixes