Design/Logic Flaw

An issue was discovered in Tor before 0.4.6.5, aka TROVE-2021-005. Hashing is mishandled for certain retrieval of circuit data. Consequently. an attacker can trigger the use of an attacker-chosen circuit ID to cause algorithm inefficiency...

CVE-2021-34549

CVE-2021-34549 affects Tor prior to 0.4.6.5. The issue is a hashtable-based CPU denial-of-service attack against relays: an attacker can exploit a naive, unkeyed hash used to look up circuits in a circuitmux to construct circuits with chosen circuit IDs, causing collisions and degraded performanc...