CVE-2019-12749
Published: 11 June 2019
dbus before 1.10.28, 1.12.x before 1.12.16, and 1.13.x before 1.13.12, as used in DBusServer in Canonical Upstart in Ubuntu 14.04 (and in some, less common, uses of dbus-daemon), allows cookie spoofing because of symlink mishandling in the reference implementation of DBUS_COOKIE_SHA1 in the libdbus library. (This only affects the DBUS_COOKIE_SHA1 authentication mechanism.) A malicious client with write access to its own home directory could manipulate a ~/.dbus-keyrings symlink to cause a DBusServer with a different uid to read and write in unintended locations. In the worst case, this could result in the DBusServer reusing a cookie that is known to the malicious client, and treating that cookie as evidence that a subsequent client connection came from an attacker-chosen uid, allowing authentication bypass.
Priority
Status
| Package | Release | Status |
|---|---|---|
|
dbus Launchpad, Ubuntu, Debian |
bionic |
Released
(1.12.2-1ubuntu1.1)
|
| cosmic |
Released
(1.12.10-1ubuntu2.1)
|
|
| disco |
Released
(1.12.12-1ubuntu1.1)
|
|
| trusty |
Released
(1.6.18-0ubuntu4.5+esm1)
Available with Ubuntu Pro or Ubuntu Pro (Infra-only) |
|
| upstream |
Needs triage
|
|
| xenial |
Released
(1.10.6-1ubuntu3.4)
|
|
|
Patches: upstream: https://gitlab.freedesktop.org/dbus/dbus/uploads/25073ca3ccbcd7839d5c0d8224e42d99/0001-auth-Reject-DBUS_COOKIE_SHA1-for-users-other-than-th.patch upstream: https://gitlab.freedesktop.org/dbus/dbus/uploads/1d0109466b4564df1ad093aad2fcebfa/0001-auth-Reject-DBUS_COOKIE_SHA1-for-users-other-than-th.patch upstream: https://gitlab.freedesktop.org/dbus/dbus/uploads/10e58a024127b230b142932c79f0a94e/0001-auth-Reject-DBUS_COOKIE_SHA1-for-users-other-than-th.patch |
||
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 7.1 |
| Attack vector | Local |
| Attack complexity | Low |
| Privileges required | Low |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | High |
| Integrity impact | High |
| Availability impact | None |
| Vector | CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N |