Vulnerabilities > CVE-2018-6791 - OS Command Injection vulnerability in multiple products
Attack vector
PHYSICAL Attack complexity
LOW Privileges required
NONE Confidentiality impact
HIGH Integrity impact
HIGH Availability impact
HIGH Summary
An issue was discovered in soliduiserver/deviceserviceaction.cpp in KDE Plasma Workspace before 5.12.0. When a vfat thumbdrive that contains `` or $() in its volume label is plugged in and mounted through the device notifier, it's interpreted as a shell command, leading to a possibility of arbitrary command execution. An example of an offending volume label is "$(touch b)" -- this will create a file called b in the home folder.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Command Line Execution through SQL Injection An attacker uses standard SQL injection methods to inject data into the command line for execution. This could be done directly through misuse of directives such as MSSQL_xp_cmdshell or indirectly through injection of data into the database that would be interpreted as shell commands. Sometime later, an unscrupulous backend application (or could be part of the functionality of the same application) fetches the injected data stored in the database and uses this data as command line arguments without performing proper validation. The malicious data escapes that data plane by spawning new commands to be executed on the host.
- Command Delimiters An attack of this type exploits a programs' vulnerabilities that allows an attacker's commands to be concatenated onto a legitimate command with the intent of targeting other resources such as the file system or database. The system that uses a filter or a blacklist input validation, as opposed to whitelist validation is vulnerable to an attacker who predicts delimiters (or combinations of delimiters) not present in the filter or blacklist. As with other injection attacks, the attacker uses the command delimiter payload as an entry point to tunnel through the application and activate additional attacks through SQL queries, shell commands, network scanning, and so on.
- Exploiting Multiple Input Interpretation Layers An attacker supplies the target software with input data that contains sequences of special characters designed to bypass input validation logic. This exploit relies on the target making multiples passes over the input data and processing a "layer" of special characters with each pass. In this manner, the attacker can disguise input that would otherwise be rejected as invalid by concealing it with layers of special/escape characters that are stripped off by subsequent processing steps. The goal is to first discover cases where the input validation layer executes before one or more parsing layers. That is, user input may go through the following logic in an application: In such cases, the attacker will need to provide input that will pass through the input validator, but after passing through parser2, will be converted into something that the input validator was supposed to stop.
- Argument Injection An attacker changes the behavior or state of a targeted application through injecting data or command syntax through the targets use of non-validated and non-filtered arguments of exposed services or methods.
- OS Command Injection In this type of an attack, an adversary injects operating system commands into existing application functions. An application that uses untrusted input to build command strings is vulnerable. An adversary can leverage OS command injection in an application to elevate privileges, execute arbitrary commands and compromise the underlying operating system.
Nessus
NASL family SuSE Local Security Checks NASL id OPENSUSE-2018-147.NASL description This update for plasma5-workspace fixes security issues and bugs. The following vulnerabilities were fixed : - CVE-2018-6790: Desktop notifications could have been used to load arbitrary remote images into Plasma, allowing for client IP discovery (boo#1079429) - CVE-2018-6791: A specially crafted file system label may have allowed execution of arbitrary code (boo#1079751) The following bugs were fixed : - Plasma could freeze with certain notifications (boo#1013550) last seen 2020-06-05 modified 2018-02-09 plugin id 106702 published 2018-02-09 reporter This script is Copyright (C) 2018-2020 Tenable Network Security, Inc. source https://www.tenable.com/plugins/nessus/106702 title openSUSE Security Update : plasma5-workspace (openSUSE-2018-147) NASL family Debian Local Security Checks NASL id DEBIAN_DSA-4116.NASL description Krzysztof Sieluzycki discovered that the notifier for removable devices in the KDE Plasma workspace performed insufficient sanitisation of FAT/VFAT volume labels, which could result in the execution of arbitrary shell commands if a removable device with a malformed disk label is mounted. last seen 2020-06-01 modified 2020-06-02 plugin id 106874 published 2018-02-20 reporter This script is Copyright (C) 2018 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/106874 title Debian DSA-4116-1 : plasma-workspace - security update NASL family Fedora Local Security Checks NASL id FEDORA_2018-337757E11F.NASL description Fix for CVE-2018-6790 CVE-2018-6791, backport crashfix for xembedsniproxy Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues. last seen 2020-06-05 modified 2018-02-21 plugin id 106907 published 2018-02-21 reporter This script is Copyright (C) 2018-2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/106907 title Fedora 26 : plasma-workspace (2018-337757e11f) NASL family Fedora Local Security Checks NASL id FEDORA_2018-FA58E0C507.NASL description Fix for CVE-2018-6790 CVE-2018-6791 Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues. last seen 2020-06-05 modified 2018-02-13 plugin id 106784 published 2018-02-13 reporter This script is Copyright (C) 2018-2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/106784 title Fedora 27 : plasma-workspace (2018-fa58e0c507) NASL family Gentoo Local Security Checks NASL id GENTOO_GLSA-201803-09.NASL description The remote host is affected by the vulnerability described in GLSA-201803-09 (KDE Plasma Workspaces: Multiple vulnerabilities) Multiple vulnerabilities have been discovered in KDE Plasma Workspaces. Please review the referenced CVE identifiers for details. Impact : An attacker could execute arbitrary commands via specially crafted thumb drive’s volume labels or obtain sensitive information via specially crafted notifications. Workaround : Users should mount removable devices with Dolphin instead of the device notifier. Users should disable notifications. last seen 2020-06-01 modified 2020-06-02 plugin id 108435 published 2018-03-19 reporter This script is Copyright (C) 2018 Tenable Network Security, Inc. source https://www.tenable.com/plugins/nessus/108435 title GLSA-201803-09 : KDE Plasma Workspaces: Multiple vulnerabilities