Vulnerabilities > CVE-2020-12769 - Improper Synchronization vulnerability in multiple products
Attack vector
LOCAL Attack complexity
LOW Privileges required
NONE Confidentiality impact
NONE Integrity impact
NONE Availability impact
COMPLETE Summary
An issue was discovered in the Linux kernel before 5.4.17. drivers/spi/spi-dw.c allows attackers to cause a panic via concurrent calls to dw_spi_irq and dw_spi_transfer_one, aka CID-19b61392c5a8.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Forced Deadlock This attack attempts to trigger and exploit a deadlock condition in the target software to cause a denial of service. A deadlock can occur when two or more competing actions are waiting for each other to finish, and thus neither ever does. Deadlock condition are not easy to detect.
- Leveraging Race Conditions This attack targets a race condition occurring when multiple processes access and manipulate the same resource concurrently and the outcome of the execution depends on the particular order in which the access takes place. The attacker can leverage a race condition by "running the race", modifying the resource and modifying the normal execution flow. For instance a race condition can occur while accessing a file, the attacker can trick the system by replacing the original file with his version and cause the system to read the malicious file.
- Leveraging Race Conditions via Symbolic Links This attack leverages the use of symbolic links (Symlinks) in order to write to sensitive files. An attacker can create a Symlink link to a target file not otherwise accessible to her. When the privileged program tries to create a temporary file with the same name as the Symlink link, it will actually write to the target file pointed to by the attackers' Symlink link. If the attacker can insert malicious content in the temporary file she will be writing to the sensitive file by using the Symlink. The race occurs because the system checks if the temporary file exists, then creates the file. The attacker would typically create the Symlink during the interval between the check and the creation of the temporary file.
- Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions This attack targets a race condition occurring between the time of check (state) for a resource and the time of use of a resource. The typical example is the file access. The attacker can leverage a file access race condition by "running the race", meaning that he would modify the resource between the first time the target program accesses the file and the time the target program uses the file. During that period of time, the attacker could do something such as replace the file and cause an escalation of privilege.
Nessus
NASL family Ubuntu Local Security Checks NASL id UBUNTU_USN-4391-1.NASL description It was discovered that the ext4 file system implementation in the Linux kernel did not properly handle setxattr operations in some situations. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-19319) It was discovered that memory contents previously stored in microarchitectural special registers after RDRAND, RDSEED, and SGX EGETKEY read operations on Intel client and Xeon E3 processors may be briefly exposed to processes on the same or different processor cores. A local attacker could use this to expose sensitive information. (CVE-2020-0543) Piotr Krysiuk discovered that race conditions existed in the file system implementation in the Linux kernel. A local attacker could use this to cause a denial of service (system crash). (CVE-2020-12114) It was discovered that the USB susbsystem last seen 2020-06-13 modified 2020-06-10 plugin id 137301 published 2020-06-10 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/137301 title Ubuntu 16.04 LTS : linux, linux-aws, linux-kvm vulnerabilities (USN-4391-1) NASL family Huawei Local Security Checks NASL id EULEROS_SA-2020-1592.NASL description According to the versions of the kernel packages installed, the EulerOS installation on the remote host is affected by the following vulnerabilities : - A flaw was found in the Linux kernel last seen 2020-06-11 modified 2020-05-26 plugin id 136870 published 2020-05-26 reporter This script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/136870 title EulerOS 2.0 SP8 : kernel (EulerOS-SA-2020-1592) NASL family Debian Local Security Checks NASL id DEBIAN_DLA-2241.NASL description This update is now available for all supported architectures. For reference the original advisory text follows. Several vulnerabilities have been discovered in the Linux kernel that may lead to a privilege escalation, denial of service or information leaks. CVE-2015-8839 A race condition was found in the ext4 filesystem implementation. A local user could exploit this to cause a denial of service (filesystem corruption). CVE-2018-14610, CVE-2018-14611, CVE-2018-14612, CVE-2018-14613 Wen Xu from SSLab at Gatech reported that crafted Btrfs volumes could trigger a crash (Oops) and/or out-of-bounds memory access. An attacker able to mount such a volume could use this to cause a denial of service or possibly for privilege escalation. CVE-2019-5108 Mitchell Frank of Cisco discovered that when the IEEE 802.11 (WiFi) stack was used in AP mode with roaming, it would trigger roaming for a newly associated station before the station was authenticated. An attacker within range of the AP could use this to cause a denial of service, either by filling up a switching table or by redirecting traffic away from other stations. CVE-2019-19319 Jungyeon discovered that a crafted filesystem can cause the ext4 implementation to deallocate or reallocate journal blocks. A user permitted to mount filesystems could use this to cause a denial of service (crash), or possibly for privilege escalation. CVE-2019-19447 It was discovered that the ext4 filesystem driver did not safely handle unlinking of an inode that, due to filesystem corruption, already has a link count of 0. An attacker able to mount arbitrary ext4 volumes could use this to cause a denial of service (memory corruption or crash) or possibly for privilege escalation. CVE-2019-19768 Tristan Madani reported a race condition in the blktrace debug facility that could result in a use-after-free. A local user able to trigger removal of block devices could possibly use this to cause a denial of service (crash) or for privilege escalation. CVE-2019-20636 The syzbot tool found that the input subsystem did not fully validate keycode changes, which could result in a heap out-of-bounds write. A local user permitted to access the device node for an input or VT device could possibly use this to cause a denial of service (crash or memory corruption) or for privilege escalation. CVE-2020-0009 Jann Horn reported that the Android ashmem driver did not prevent read-only files from being memory-mapped and then remapped as read-write. However, Android drivers are not enabled in Debian kernel configurations. CVE-2020-0543 Researchers at VU Amsterdam discovered that on some Intel CPUs supporting the RDRAND and RDSEED instructions, part of a random value generated by these instructions may be used in a later speculative execution on any core of the same physical CPU. Depending on how these instructions are used by applications, a local user or VM guest could use this to obtain sensitive information such as cryptographic keys from other users or VMs. This vulnerability can be mitigated by a microcode update, either as part of system firmware (BIOS) or through the intel-microcode package in Debian last seen 2020-06-13 modified 2020-06-10 plugin id 137283 published 2020-06-10 reporter This script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/137283 title Debian DLA-2241-2 : linux security update NASL family Slackware Local Security Checks NASL id SLACKWARE_SSA_2020-163-01.NASL description New kernel packages are available for Slackware 14.2 to fix security issues. last seen 2020-06-13 modified 2020-06-12 plugin id 137391 published 2020-06-12 reporter This script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/137391 title Slackware 14.2 : Slackware 14.2 kernel (SSA:2020-163-01)
References
- https://lkml.org/lkml/2020/2/3/559
- https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4.17
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=19b61392c5a852b4e8a0bf35aecb969983c5932d
- https://security.netapp.com/advisory/ntap-20200608-0001/
- https://lists.debian.org/debian-lts-announce/2020/06/msg00011.html
- https://lists.debian.org/debian-lts-announce/2020/06/msg00013.html
- http://lists.opensuse.org/opensuse-security-announce/2020-06/msg00022.html
- https://usn.ubuntu.com/4391-1/
- http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00008.html