CVE-2019-12749 Information

Description

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.

CVSS Vector

CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Reference

http://lists.opensuse.org/opensuse-security-announce/2019-06/msg00059.html http://lists.opensuse.org/opensuse-security-announce/2019-06/msg00092.html http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00026.html http://www.openwall.com/lists/oss-security/2019/06/11/2 http://www.securityfocus.com/bid/108751 https://access.redhat.com/errata/RHSA-2019:1726 https://access.redhat.com/errata/RHSA-2019:2868 https://access.redhat.com/errata/RHSA-2019:2870 https://access.redhat.com/errata/RHSA-2019:3707 https://lists.debian.org/debian-lts-announce/2019/06/msg00005.html https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/V2CQF37O73VH2JDVX2ILX2KD2KLXLQOU/ https://seclists.org/bugtraq/2019/Jun/16 https://security.gentoo.org/glsa/201909-08 https://usn.ubuntu.com/4015-1/ https://usn.ubuntu.com/4015-2/ https://www.debian.org/security/2019/dsa-4462 https://www.openwall.com/lists/oss-security/2019/06/11/2

Attack Complexity

LOW

Privileges Required

LOW

User Interaction Required

LOW

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

NONE

Base Severity

7.1