Several security issues were fixed in the Linux kernel.
It was discovered that the btrfs implementation in the Linux kernel did not properly detect that a block was marked dirty in some situations. An attacker could use this to specially craft a file system image that, when unmounted, could cause a denial of service (system crash). (CVE-2019-19377)
21 May 2020
A security issue affects these releases of Ubuntu and its derivatives:
Several security issues were fixed in the Linux kernel.
It was discovered that the btrfs implementation in the Linux kernel did not properly detect that a block was marked dirty in some situations. An attacker could use this to specially craft a file system image that, when unmounted, could cause a denial of service (system crash). (CVE-2019-19377)
Tristan Madani discovered that the file locking implementation in the Linux kernel contained a race condition. A local attacker could possibly use this to cause a denial of service or expose sensitive information. (CVE-2019-19769)
It was discovered that the Serial CAN interface driver in the Linux kernel did not properly initialize data. A local attacker could use this to expose sensitive information (kernel memory). (CVE-2020-11494)
It was discovered that the linux kernel did not properly validate certain mount options to the tmpfs virtual memory file system. A local attacker with the ability to specify mount options could use this to cause a denial of service (system crash). (CVE-2020-11565)
It was discovered that the OV51x USB Camera device driver in the Linux kernel did not properly validate device metadata. A physically proximate attacker could use this to cause a denial of service (system crash). (CVE-2020-11608)
It was discovered that the STV06XX USB Camera device driver in the Linux kernel did not properly validate device metadata. A physically proximate attacker could use this to cause a denial of service (system crash). (CVE-2020-11609)
It was discovered that the Xirlink C-It USB Camera device driver in the Linux kernel did not properly validate device metadata. A physically proximate attacker could use this to cause a denial of service (system crash). (CVE-2020-11668)
It was discovered that the block layer in the Linux kernel contained a race condition leading to a use-after-free vulnerability. A local attacker could possibly use this to cause a denial of service (system crash) or execute arbitrary code. (CVE-2020-12657)
The problem can be corrected by updating your system to the following package versions:
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
After a standard system update you need to reboot your computer to make all the necessary changes.
ATTENTION: Due to an unavoidable ABI change the kernel updates have been given a new version number, which requires you to recompile and reinstall all third party kernel modules you might have installed. Unless you manually uninstalled the standard kernel metapackages (e.g. linux-generic, linux-generic-lts-RELEASE, linux-virtual, linux-powerpc), a standard system upgrade will automatically perform this as well.
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