Torproject Tor CVEs.

Tor before 0.4.9.7 has an out-of-bounds read when an END, a TRUNCATE, or a TRUNCATED cell lacks a reason in its payload, aka TROVE-2026-011.

Torproject Tor

Tor before 0.4.9.11 is prone to a use-after-free (and potential double free) of a conflux object when a recovery leg revives a conflux set whose last linked leg has already been closed. A malicious exit node could use this to crash a client. This is TROVE-2026-026.

Memory safety Torproject Tor

Tor before 0.4.9.9 was prone to a compression bomb bypass where an attacker could concatenate many gzip or zlib sub-streams, each just under the per-stream detection threshold, to avoid the compression bomb check entirely. This is TROVE-2026-022.

Other Torproject Tor

tor before 0.4.9.9 was prone to an infinite loop when decompressing a truncated zlib/gzip stream with done=1. A truncated stream never reaches Z_STREAM_END, causing zlib to return Z_BUF_ERROR with no input remaining, which buf_add_compress() mistook for a full output buffer and retried forever. Fixed by returning TOR_COMPRESS_ERROR in that case so the caller can abort cleanly. This is TROVE-2026-021.

Other Torproject Tor

Tor before 0.4.9.7 mishandles accounting of the conflux out-of-order queue during the clearing of a queue, aka TROVE-2026-010.

Torproject Tor

tor before 0.4.9.9 was prone to a NULL write after free when sending a CONFLUX_SWITCH cell fails. The return value of relay_send_command_from_edge() was ignored, so a send failure (which calls circuit_mark_for_close() and removes the leg via cfx_del_leg()) would go undetected, causing the caller to write to the now-freed current leg and resulting in a crash. This is TROVE-2026-017.

Denial of service Torproject Tor

tor before 0.4.9.9 was prone to an out-of-bounds write when parsing a consensus or detached signature with unexpected signature digest type. Impact is minor for most Tor roles, but potentially major for directory authorities. This is TROVE-2026-019.

Memory safety Torproject Tor

Tor before 0.4.9.7 has an out-of-bounds read by one byte via a malformed BEGIN cell, aka TROVE-2026-007.

Torproject Tor

Tor before 0.4.9.7, when circuit queue memory pressure exists, can experience a client crash because of a double close of a circuit, aka TROVE-2026-009.

Torproject Tor

Tor before 0.4.9.7 has a NULL pointer dereference when a CERT cell is received out of order, aka TROVE-2026-006.

Torproject Tor

Tor before 0.4.9.11 is prone to a race condition where in just the right circumstances a rendezvous point could man-in-the-middle (impersonate) the onion service that the client was trying to reach.

Other Torproject Tor

Tor before 0.4.9.7 can attempt or accept BEGIN_DIR via conflux legs, aka TROVE-2026-008.

Torproject Tor

Tor before 0.4.9.10 did not reject a CONFLUX_LINK cell that arrives on a circuit which already has attached streams. A malicious client could send a RELAY_COMMAND_BEGIN before the CONFLUX_LINK on the same circuit, attaching an exit stream that would later end up orphan leaving a dangling circuit back-pointer and a use-after-free (UAF) when the circuit is freed. This is TROVE-2026-025.

Memory safety Torproject Tor