[ASA-201906-16] dbus: access restriction bypass
Arch Linux Security Advisory ASA-201906-16 ========================================== Severity: High Date : 2019-06-18 CVE-ID : CVE-2019-12749 Package : dbus Type : access restriction bypass Remote : No Link : https://security.archlinux.org/AVG-974 Summary ======= The package dbus before version 1.12.16-1 is vulnerable to access restriction bypass. Resolution ========== Upgrade to 1.12.16-1. # pacman -Syu "dbus>=1.12.16-1" The problem has been fixed upstream in version 1.12.16. Workaround ========== None. Description =========== It has been discovered that dbus before 1.12.16 allows cookie spoofing because of symlink mishandling in the reference implementation of DBUS_COOKIE_SHA1 in the libdbus library. This issue 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. Impact ====== A local attacker could use this issue to bypass authentication and escalate privileges. References ========== https://www.openwall.com/lists/oss-security/2019/06/11/2 https://gitlab.freedesktop.org/dbus/dbus/issues/269 https://gitlab.freedesktop.org/dbus/dbus/commit/47b1a4c41004bf494b87370987b2... https://security.archlinux.org/CVE-2019-12749
participants (1)
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Levente Polyak