CVE-2017-8819

Publication date 3 December 2017

Last updated 24 July 2024


Ubuntu priority

Cvss 3 Severity Score

7.5 · High

Score breakdown

In Tor before 0.2.5.16, 0.2.6 through 0.2.8 before 0.2.8.17, 0.2.9 before 0.2.9.14, 0.3.0 before 0.3.0.13, and 0.3.1 before 0.3.1.9, the replay-cache protection mechanism is ineffective for v2 onion services, aka TROVE-2017-009. An attacker can send many INTRODUCE2 cells to trigger this issue.

From the Ubuntu Security Team

It was discovered that the replay-cache protection mechanism used by Tor is ineffective for v2 onion services. An attacker could possible use this to facilitate a traffic confirmation attack.

Status

Package Ubuntu Release Status
tor 18.10 cosmic
Not affected
18.04 LTS bionic
Not affected
17.10 artful
Fixed 0.3.0.13-0ubuntu1~17.10.2
17.04 zesty Ignored end of life
16.04 LTS xenial
Fixed 0.2.9.14-1ubuntu1~16.04.2
14.04 LTS trusty
Fixed 0.2.4.27-1ubuntu0.1

Severity score breakdown

Parameter Value
Base score 7.5 · High
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Scope Unchanged
Confidentiality None
Integrity impact None
Availability impact High
Vector CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H