Vulnerabilities > CVE-2020-8832 - Information Exposure vulnerability in multiple products
Attack vector
LOCAL Attack complexity
LOW Privileges required
LOW Confidentiality impact
HIGH Integrity impact
NONE Availability impact
NONE Summary
The fix for the Linux kernel in Ubuntu 18.04 LTS for CVE-2019-14615 ("The Linux kernel did not properly clear data structures on context switches for certain Intel graphics processors.") was discovered to be incomplete, meaning that in versions of the kernel before 4.15.0-91.92, an attacker could use this vulnerability to expose sensitive information.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Subverting Environment Variable Values The attacker directly or indirectly modifies environment variables used by or controlling the target software. The attacker's goal is to cause the target software to deviate from its expected operation in a manner that benefits the attacker.
- Footprinting An attacker engages in probing and exploration activity to identify constituents and properties of the target. Footprinting is a general term to describe a variety of information gathering techniques, often used by attackers in preparation for some attack. It consists of using tools to learn as much as possible about the composition, configuration, and security mechanisms of the targeted application, system or network. Information that might be collected during a footprinting effort could include open ports, applications and their versions, network topology, and similar information. While footprinting is not intended to be damaging (although certain activities, such as network scans, can sometimes cause disruptions to vulnerable applications inadvertently) it may often pave the way for more damaging attacks.
- Exploiting Trust in Client (aka Make the Client Invisible) An attack of this type exploits a programs' vulnerabilities in client/server communication channel authentication and data integrity. It leverages the implicit trust a server places in the client, or more importantly, that which the server believes is the client. An attacker executes this type of attack by placing themselves in the communication channel between client and server such that communication directly to the server is possible where the server believes it is communicating only with a valid client. There are numerous variations of this type of attack.
- Browser Fingerprinting An attacker carefully crafts small snippets of Java Script to efficiently detect the type of browser the potential victim is using. Many web-based attacks need prior knowledge of the web browser including the version of browser to ensure successful exploitation of a vulnerability. Having this knowledge allows an attacker to target the victim with attacks that specifically exploit known or zero day weaknesses in the type and version of the browser used by the victim. Automating this process via Java Script as a part of the same delivery system used to exploit the browser is considered more efficient as the attacker can supply a browser fingerprinting method and integrate it with exploit code, all contained in Java Script and in response to the same web page request by the browser.
- Session Credential Falsification through Prediction This attack targets predictable session ID in order to gain privileges. The attacker can predict the session ID used during a transaction to perform spoofing and session hijacking.
Nessus
| NASL family | Ubuntu Local Security Checks |
| NASL id | UBUNTU_USN-4302-1.NASL |
| description | Paulo Bonzini discovered that the KVM hypervisor implementation in the Linux kernel could improperly let a nested (level 2) guest access the resources of a parent (level 1) guest in certain situations. An attacker could use this to expose sensitive information. (CVE-2020-2732) Gregory Herrero discovered that the fix for CVE-2019-14615 to address the Linux kernel not properly clearing data structures on context switches for certain Intel graphics processors was incomplete. A local attacker could use this to expose sensitive information. (CVE-2020-8832) It was discovered that the IPMI message handler implementation in the Linux kernel did not properly deallocate memory in certain situations. A local attacker could use this to cause a denial of service (kernel memory exhaustion). (CVE-2019-19046) It was discovered that the Intel WiMAX 2400 driver in the Linux kernel did not properly deallocate memory in certain situations. A local attacker could use this to cause a denial of service (kernel memory exhaustion). (CVE-2019-19051) It was discovered that the Marvell Wi-Fi device driver in the Linux kernel did not properly deallocate memory in certain error conditions. A local attacker could use this to possibly cause a denial of service (kernel memory exhaustion). (CVE-2019-19056) It was discovered that the Intel(R) Wi-Fi device driver in the Linux kernel device driver in the Linux kernel did not properly deallocate memory in certain error conditions. A local attacker could possibly use this to cause a denial of service (kernel memory exhaustion). (CVE-2019-19058) It was discovered that the Brocade BFA Fibre Channel device driver in the Linux kernel did not properly deallocate memory in certain error conditions. A local attacker could possibly use this to cause a denial of service (kernel memory exhaustion). (CVE-2019-19066) It was discovered that the Realtek RTL8xxx USB Wi-Fi device driver in the Linux kernel did not properly deallocate memory in certain error conditions. A local attacker could possibly use this to cause a denial of service (kernel memory exhaustion). (CVE-2019-19068) It was discovered that ZR364XX Camera USB device driver for the Linux kernel did not properly initialize memory. A physically proximate attacker could use this to cause a denial of service (system crash). (CVE-2019-15217). Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues. |
| last seen | 2020-04-16 |
| modified | 2020-03-18 |
| plugin id | 134660 |
| published | 2020-03-18 |
| reporter | Ubuntu Security Notice (C) 2020 Canonical, Inc. / NASL script (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof. |
| source | https://www.tenable.com/plugins/nessus/134660 |
| title | Ubuntu 16.04 LTS / 18.04 LTS : linux, linux-aws, linux-aws-hwe, linux-gcp, linux-gke-4.15, linux-hwe, (USN-4302-1) |
| code | |
References
- https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1862840
- https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1862840
- https://security.netapp.com/advisory/ntap-20200430-0004/
- https://security.netapp.com/advisory/ntap-20200430-0004/
- https://usn.ubuntu.com/usn/usn-4302-1
- https://usn.ubuntu.com/usn/usn-4302-1