torproject CVE Vulnerabilities & Metrics

Focus on torproject vulnerabilities and metrics.

Last updated: 08 Mar 2025, 23:25 UTC

About torproject Security Exposure

This page consolidates all known Common Vulnerabilities and Exposures (CVEs) associated with torproject. We track both calendar-based metrics (using fixed periods) and rolling metrics (using gliding windows) to give you a comprehensive view of security trends and risk evolution. Use these insights to assess risk and plan your patching strategy.

For a broader perspective on cybersecurity threats, explore the comprehensive list of CVEs by vendor and product. Stay updated on critical vulnerabilities affecting major software and hardware providers.

Global CVE Overview

Total torproject CVEs: 33
Earliest CVE date: 14 Sep 2012, 18:55 UTC
Latest CVE date: 14 Jan 2023, 01:15 UTC

Latest CVE reference: CVE-2023-23589

Rolling Stats

30-day Count (Rolling): 0
365-day Count (Rolling): 0

Calendar-based Variation

Calendar-based Variation compares a fixed calendar period (e.g., this month versus the same month last year), while Rolling Growth Rate uses a continuous window (e.g., last 30 days versus the previous 30 days) to capture trends independent of calendar boundaries.

Variations & Growth

Month Variation (Calendar): 0%
Year Variation (Calendar): 0%

Month Growth Rate (30-day Rolling): 0.0%
Year Growth Rate (365-day Rolling): 0.0%

Monthly CVE Trends (current vs previous Year)

Annual CVE Trends (Last 20 Years)

Critical torproject CVEs (CVSS ≥ 9) Over 20 Years

CVSS Stats

Average CVSS: 4.68

Max CVSS: 7.8

Critical CVEs (≥9): 0

CVSS Range vs. Count

Range Count
0.0-3.9 4
4.0-6.9 34
7.0-8.9 2
9.0-10.0 0

CVSS Distribution Chart

Top 5 Highest CVSS torproject CVEs

These are the five CVEs with the highest CVSS scores for torproject, sorted by severity first and recency.

All CVEs for torproject

CVE-2023-23589 torproject vulnerability CVSS: 0 14 Jan 2023, 01:15 UTC

The SafeSocks option in Tor before 0.4.7.13 has a logic error in which the unsafe SOCKS4 protocol can be used but not the safe SOCKS4a protocol, aka TROVE-2022-002.

CVE-2022-33903 torproject vulnerability CVSS: 0 17 Jul 2022, 23:15 UTC

Tor 0.4.7.x before 0.4.7.8 allows a denial of service via the wedging of RTT estimation.

CVE-2021-46702 torproject vulnerability CVSS: 2.1 26 Feb 2022, 03:15 UTC

Tor Browser 9.0.7 on Windows 10 build 10586 is vulnerable to information disclosure. This could allow local attackers to bypass the intended anonymity feature and obtain information regarding the onion services visited by a local user. This can be accomplished by analyzing RAM memory even several hours after the local user used the product. This occurs because the product doesn't properly free memory.

CVE-2021-39246 torproject vulnerability CVSS: 3.6 24 Sep 2021, 19:15 UTC

Tor Browser through 10.5.6 and 11.x through 11.0a4 allows a correlation attack that can compromise the privacy of visits to v2 onion addresses. Exact timestamps of these onion-service visits are logged locally, and an attacker might be able to compare them to timestamp data collected by the destination server (or collected by a rogue site within the Tor network).

CVE-2021-38385 torproject vulnerability CVSS: 5.0 30 Aug 2021, 05:15 UTC

Tor before 0.3.5.16, 0.4.5.10, and 0.4.6.7 mishandles the relationship between batch-signature verification and single-signature verification, leading to a remote assertion failure, aka TROVE-2021-007.

CVE-2021-34550 torproject vulnerability CVSS: 5.0 29 Jun 2021, 12:15 UTC

An issue was discovered in Tor before 0.4.6.5, aka TROVE-2021-006. The v3 onion service descriptor parsing allows out-of-bounds memory access, and a client crash, via a crafted onion service descriptor

CVE-2021-34549 torproject vulnerability CVSS: 5.0 29 Jun 2021, 12:15 UTC

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-2021-34548 torproject vulnerability CVSS: 5.0 29 Jun 2021, 11:15 UTC

An issue was discovered in Tor before 0.4.6.5, aka TROVE-2021-003. An attacker can forge RELAY_END or RELAY_RESOLVED to bypass the intended access control for ending a stream.

CVE-2021-28090 torproject vulnerability CVSS: 5.0 19 Mar 2021, 05:15 UTC

Tor before 0.4.5.7 allows a remote attacker to cause Tor directory authorities to exit with an assertion failure, aka TROVE-2021-002.

CVE-2021-28089 torproject vulnerability CVSS: 5.0 19 Mar 2021, 05:15 UTC

Tor before 0.4.5.7 allows a remote participant in the Tor directory protocol to exhaust CPU resources on a target, aka TROVE-2021-001.

CVE-2020-15572 torproject vulnerability CVSS: 4.3 15 Jul 2020, 17:15 UTC

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.

CVE-2020-10593 torproject vulnerability CVSS: 5.0 23 Mar 2020, 13:15 UTC

Tor before 0.3.5.10, 0.4.x before 0.4.1.9, and 0.4.2.x before 0.4.2.7 allows remote attackers to cause a Denial of Service (memory leak), aka TROVE-2020-004. This occurs in circpad_setup_machine_on_circ because a circuit-padding machine can be negotiated twice on the same circuit.

CVE-2020-10592 torproject vulnerability CVSS: 7.8 23 Mar 2020, 13:15 UTC

Tor before 0.3.5.10, 0.4.x before 0.4.1.9, and 0.4.2.x before 0.4.2.7 allows remote attackers to cause a Denial of Service (CPU consumption), aka TROVE-2020-002.

CVE-2020-8516 torproject vulnerability CVSS: 5.0 02 Feb 2020, 13:15 UTC

The daemon in Tor through 0.4.1.8 and 0.4.2.x through 0.4.2.6 does not verify that a rendezvous node is known before attempting to connect to it, which might make it easier for remote attackers to discover circuit information. NOTE: The network team of Tor claims this is an intended behavior and not a vulnerability

CVE-2015-2929 torproject vulnerability CVSS: 5.0 24 Jan 2020, 18:15 UTC

The Hidden Service (HS) client implementation in Tor before 0.2.4.27, 0.2.5.x before 0.2.5.12, and 0.2.6.x before 0.2.6.7 allows remote servers to cause a denial of service (assertion failure and application exit) via a malformed HS descriptor.

CVE-2015-2928 torproject vulnerability CVSS: 5.0 24 Jan 2020, 18:15 UTC

The Hidden Service (HS) server implementation in Tor before 0.2.4.27, 0.2.5.x before 0.2.5.12, and 0.2.6.x before 0.2.6.7 allows remote attackers to cause a denial of service (assertion failure and daemon exit) via unspecified vectors.

CVE-2015-2689 torproject vulnerability CVSS: 5.0 24 Jan 2020, 18:15 UTC

Tor before 0.2.4.26 and 0.2.5.x before 0.2.5.11 does not properly handle pending-connection resolve states during periods of high DNS load, which allows remote attackers to cause a denial of service (assertion failure and daemon exit) via crafted packets.

CVE-2015-2688 torproject vulnerability CVSS: 5.0 24 Jan 2020, 18:15 UTC

buf_pullup in Tor before 0.2.4.26 and 0.2.5.x before 0.2.5.11 does not properly handle unexpected arrival times of buffers with invalid layouts, which allows remote attackers to cause a denial of service (assertion failure and daemon exit) via crafted packets.

CVE-2019-13075 torproject vulnerability CVSS: 5.0 30 Jun 2019, 14:15 UTC

Tor Browser through 8.5.3 has an information exposure vulnerability. It allows remote attackers to detect the browser's language via vectors involving an IFRAME element, because text in that language is included in the title attribute of a LINK element for a non-HTML page. This is related to a behavior of Firefox before 68.

CVE-2019-12383 torproject vulnerability CVSS: 4.3 28 May 2019, 03:29 UTC

Tor Browser before 8.0.1 has an information exposure vulnerability. It allows remote attackers to detect the browser's UI locale by measuring a button width, even if the user has a "Don't send my language" setting.

CVE-2019-8955 torproject vulnerability CVSS: 5.0 21 Feb 2019, 23:29 UTC

In Tor before 0.3.3.12, 0.3.4.x before 0.3.4.11, 0.3.5.x before 0.3.5.8, and 0.4.x before 0.4.0.2-alpha, remote denial of service against Tor clients and relays can occur via memory exhaustion in the KIST cell scheduler.

CVE-2017-16639 torproject vulnerability CVSS: 4.3 14 Sep 2018, 21:29 UTC

Tor Browser on Windows before 8.0 allows remote attackers to bypass the intended anonymity feature and discover a client IP address, a different vulnerability than CVE-2017-16541. User interaction is required to trigger this vulnerability.

CVE-2018-16983 torproject vulnerability CVSS: 7.5 13 Sep 2018, 04:29 UTC

NoScript Classic before 5.1.8.7, as used in Tor Browser 7.x and other products, allows attackers to bypass script blocking via the text/html;/json Content-Type value.

CVE-2016-9079 torproject vulnerability CVSS: 5.0 11 Jun 2018, 21:29 UTC

A use-after-free vulnerability in SVG Animation has been discovered. An exploit built on this vulnerability has been discovered in the wild targeting Firefox and Tor Browser users on Windows. This vulnerability affects Firefox < 50.0.2, Firefox ESR < 45.5.1, and Thunderbird < 45.5.1.

CVE-2018-0491 torproject vulnerability CVSS: 5.0 05 Mar 2018, 15:29 UTC

A use-after-free issue was discovered in Tor 0.3.2.x before 0.3.2.10. It allows remote attackers to cause a denial of service (relay crash) because the KIST implementation allows a channel to be added more than once in the pending list.

CVE-2018-0490 torproject vulnerability CVSS: 5.0 05 Mar 2018, 15:29 UTC

An issue was discovered in Tor before 0.2.9.15, 0.3.1.x before 0.3.1.10, and 0.3.2.x before 0.3.2.10. The directory-authority protocol-list subprotocol implementation allows remote attackers to cause a denial of service (NULL pointer dereference and directory-authority crash) via a misformatted relay descriptor that is mishandled during voting.

CVE-2016-1254 torproject vulnerability CVSS: 5.0 05 Dec 2017, 16:29 UTC

Tor before 0.2.8.12 might allow remote attackers to cause a denial of service (client crash) via a crafted hidden service descriptor.

CVE-2017-16541 torproject vulnerability CVSS: 4.3 04 Nov 2017, 18:29 UTC

Tor Browser before 7.0.9 on macOS and Linux allows remote attackers to bypass the intended anonymity feature and discover a client IP address via vectors involving a crafted web site that leverages file:// mishandling in Firefox, aka TorMoil. NOTE: Tails is unaffected.

CVE-2017-0380 torproject vulnerability CVSS: 4.3 18 Sep 2017, 16:29 UTC

The rend_service_intro_established function in or/rendservice.c in Tor before 0.2.8.15, 0.2.9.x before 0.2.9.12, 0.3.0.x before 0.3.0.11, 0.3.1.x before 0.3.1.7, and 0.3.2.x before 0.3.2.1-alpha, when SafeLogging is disabled, allows attackers to obtain sensitive information by leveraging access to the log files of a hidden service, because uninitialized stack data is included in an error message about construction of an introduction point circuit.

CVE-2017-0377 torproject vulnerability CVSS: 5.0 02 Jul 2017, 15:29 UTC

Tor 0.3.x before 0.3.0.9 has a guard-selection algorithm that only considers the exit relay (not the exit relay's family), which might allow remote attackers to defeat intended anonymity properties by leveraging the existence of large families.

CVE-2017-0376 torproject vulnerability CVSS: 5.0 09 Jun 2017, 17:29 UTC

The hidden-service feature in Tor before 0.3.0.8 allows a denial of service (assertion failure and daemon exit) in the connection_edge_process_relay_cell function via a BEGIN_DIR cell on a rendezvous circuit.

CVE-2017-0375 torproject vulnerability CVSS: 5.0 09 Jun 2017, 17:29 UTC

The hidden-service feature in Tor before 0.3.0.8 allows a denial of service (assertion failure and daemon exit) in the relay_send_end_cell_from_edge_ function via a malformed BEGIN cell.

CVE-2016-8860 torproject vulnerability CVSS: 5.0 04 Jan 2017, 20:59 UTC

Tor before 0.2.8.9 and 0.2.9.x before 0.2.9.4-alpha had internal functions that were entitled to expect that buf_t data had NUL termination, but the implementation of or/buffers.c did not ensure that NUL termination was present, which allows remote attackers to cause a denial of service (client, hidden service, relay, or authority crash) via crafted data.

CVE-2014-5117 torproject vulnerability CVSS: 5.8 30 Jul 2014, 16:55 UTC

Tor before 0.2.4.23 and 0.2.5 before 0.2.5.6-alpha maintains a circuit after an inbound RELAY_EARLY cell is received by a client, which makes it easier for remote attackers to conduct traffic-confirmation attacks by using the pattern of RELAY and RELAY_EARLY cells as a means of communicating information about hidden service names.

CVE-2012-2250 torproject vulnerability CVSS: 5.0 03 Feb 2014, 03:55 UTC

Tor before 0.2.3.24-rc allows remote attackers to cause a denial of service (assertion failure and daemon exit) by performing link protocol negotiation incorrectly.

CVE-2012-2249 torproject vulnerability CVSS: 5.0 03 Feb 2014, 03:55 UTC

Tor before 0.2.3.23-rc allows remote attackers to cause a denial of service (assertion failure and daemon exit) via a renegotiation attempt that occurs after the initiation of the V3 link protocol.

CVE-2013-7295 torproject vulnerability CVSS: 4.0 17 Jan 2014, 21:55 UTC

Tor before 0.2.4.20, when OpenSSL 1.x is used in conjunction with a certain HardwareAccel setting on Intel Sandy Bridge and Ivy Bridge platforms, does not properly generate random numbers for (1) relay identity keys and (2) hidden-service identity keys, which might make it easier for remote attackers to bypass cryptographic protection mechanisms via unspecified vectors.

CVE-2012-5573 torproject vulnerability CVSS: 5.0 01 Jan 2013, 12:35 UTC

The connection_edge_process_relay_cell function in or/relay.c in Tor before 0.2.3.25 maintains circuits even if an unexpected SENDME cell arrives, which might allow remote attackers to cause a denial of service (memory consumption or excessive cell reception rate) or bypass intended flow-control restrictions via a RELAY_COMMAND_SENDME command.

CVE-2012-4922 torproject vulnerability CVSS: 5.0 14 Sep 2012, 18:55 UTC

The tor_timegm function in common/util.c in Tor before 0.2.2.39, and 0.2.3.x before 0.2.3.22-rc, does not properly validate time values, which allows remote attackers to cause a denial of service (assertion failure and daemon exit) via a malformed directory object, a different vulnerability than CVE-2012-4419.

CVE-2012-4419 torproject vulnerability CVSS: 5.0 14 Sep 2012, 18:55 UTC

The compare_tor_addr_to_addr_policy function in or/policies.c in Tor before 0.2.2.39, and 0.2.3.x before 0.2.3.21-rc, allows remote attackers to cause a denial of service (assertion failure and daemon exit) via a zero-valued port field that is not properly handled during policy comparison.