Torproject

By the Year

In 2026 there have been 13 vulnerabilities in Torproject with an average score of 5.2 out of ten. Last year, in 2025 Torproject had 1 security vulnerability published. That is, 12 more vulnerabilities have already been reported in 2026 as compared to last year. However, the average CVE base score of the vulnerabilities in 2026 is greater by 1.45.

Recent Torproject Security Vulnerabilities

CVE	Date	Vulnerability	Products
CVE-2026-77642	Aug 20, 2026	Tor OOB Write in Consensus parsing before 0.4.9.9 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.	Tor
CVE-2026-77641	Aug 20, 2026	Tor <0.4.9.9 NULL Write After Free in relay_send_command_from_edge 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.	Tor
CVE-2026-77640	Aug 20, 2026	Tor <0.4.9.9: Infinite loop decompressing truncated zlib/gzip 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.	Tor
CVE-2026-77639	Aug 20, 2026	Tor pre-0.4.9.9 Compression Bomb Bypass via gzip/zlib Concatenation 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.	Tor
CVE-2026-77638	Aug 20, 2026	Tor <0.4.9.11 Rendezvous MITM Race Condition 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.	Tor
CVE-2026-77587	Aug 20, 2026	Tor Use-After-Free in conflux component before 0.4.9.11 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.	Tor
CVE-2026-77584	Aug 20, 2026	Tor <0.4.9.10 Use-after-Free via CONFLUX_LINK cell 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.	Tor
CVE-2026-44603	May 07, 2026	Tor before 0.4.9.7 OOB Read via Malformed BEGIN Cell Tor before 0.4.9.7 has an out-of-bounds read by one byte via a malformed BEGIN cell, aka TROVE-2026-007.	Tor
CVE-2026-44602	May 07, 2026	Tor <0.4.9.7 NULL Pointer Deref on CERT cell out-of-order Tor before 0.4.9.7 has a NULL pointer dereference when a CERT cell is received out of order, aka TROVE-2026-006.	Tor
CVE-2026-44601	May 07, 2026	Tor 0.4.9.x DoubleClose Client Crash due to Circuit Queue Pressure 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.	Tor