tor: allows breaking its anonymity via single cell

Tor 0.2.0.28, and probably 0.2.0.34 and earlier, allows remote attackers, with control of an entry router and an exit router, to confirm that a sender and receiver are communicating via vectors involving (1) replaying, (2) modifying, (3) inserting, or (4) deleting a single cell, and then observing cell recognition errors at the exit router. NOTE: the vendor disputes the significance of this issue, noting that the product's design "accepted end-to-end correlation as an attack that is too expensive to solve."

Tor before 0.1.2.14 can construct circuits in which an entry guard is in the same family as the exit node, which might compromise the anonymity of traffic sources and destinations by exposing traffic to inappropriate remote observers.

Tor before 0.1.2.16, when ControlPort is enabled, does not properly restrict commands to localhost port 9051, which allows remote attackers to modify the torrc configuration file, compromise anonymity, and have other unspecified impact via HTTP POST data containing commands without valid authentication, as demonstrated by an HTML form (1) hosted on a web site or (2) injected by a Tor exit node.

Unspecified vulnerability in Tor before 0.2.0.33 has unspecified impact and remote attack vectors that trigger heap corruption.

Unspecified vulnerability in Tor before 0.2.0.34 allows directory mirrors to cause a denial of service (exit node crash) via "malformed input."

The connection_edge_process_relay_cell_not_open function in src/or/relay.c in Tor 0.2.x before 0.2.0.35 and 0.1.x before 0.1.2.8-beta allows exit relays to have an unspecified impact by causing controllers to accept DNS responses that redirect to an internal IP address via unknown vectors. NOTE: some of these details are obtained from third party information.

Tor before 0.1.2.15 sends "destroy cells" containing the reason for tearing down a circuit, which allows remote attackers to obtain sensitive information, contrary to specifications.

Tor before 0.1.2.15 does not properly distinguish "streamids from different exits," which might allow remote attackers with control over Tor routers to inject cells into arbitrary streams.

tor: does not properly process User/Group configuration options (privilege escalation)

Tor before 0.2.0.32 does not properly process the (1) User and (2) Group configuration options, which might allow local users to gain privileges by leveraging unintended supplementary group memberships of the Tor process.

tor: does not properly process the ClientDNSRejectInternalAddresses configuration option

Tor before 0.2.0.32 does not properly process the ClientDNSRejectInternalAddresses configuration option in situations where an exit relay issues a policy-based refusal of a stream, which allows remote exit relays to have an unknown impact by mapping an internal IP address to the destination hostname of a refused stream.

Unspecified vulnerability in Tor before 0.2.0.34 allows attackers to cause a denial of service (infinite loop) via "corrupt votes."

Unspecified vulnerability in Tor before 0.2.0.34 allows directory mirrors to cause a denial of service via unknown vectors.

Tor before 0.2.0.34 treats incomplete IPv4 addresses as valid, which has unknown impact and attack vectors related to "Spec conformance," as demonstrated using 192.168.0.

Tor before 0.2.0.35 allows remote attackers to cause a denial of service (application crash) via a malformed router descriptor.

Tor before 0.1.2.15 can select a guard node beyond the first listed never-before-connected-to guard node, which allows remote attackers with control of certain guard nodes to obtain sensitive information and possibly leverage further attacks.

Buffer overflow in Tor before 0.1.2.15, when using BSD natd support, allows remote attackers to cause a denial of service via unspecified vectors.

Tor allows remote attackers to discover the IP address of a hidden service by accessing this service at a high rate, thereby changing the server's CPU temperature and consequently changing the pattern of time values visible through (1) ICMP timestamps, (2) TCP sequence numbers, and (3) TCP timestamps, a different vulnerability than CVE-2006-0414. NOTE: it could be argued that this is a laws-of-physics vulnerability that is a fundamental design limitation of certain hardware implementations, so perhaps this issue should not be included in CVE.

Tor does not verify a node's uptime and bandwidth advertisements, which allows remote attackers who operate a low resource node to make false claims of greater resources, which places the node into use for many circuits and compromises the anonymity of traffic sources and destinations.

Tor before 0.1.1.20 does not validate that a server descriptor's fingerprint line matches its identity key, which allows remote attackers to spoof the fingerprint line, which might be trusted by users or other applications.

Tor client before 0.1.1.20 prefers entry points based on is_fast or is_stable flags, which could allow remote attackers to be preferred over nodes that are identified as more trustworthy "entry guard" (is_guard) systems by directory authorities.