Packages
- linux - Linux kernel
- linux-hwe-5.4 - Linux hardware enablement (HWE) kernel
- linux-hwe-5.8 - Linux hardware enablement (HWE) kernel
Details
USN-4576-1 fixed a vulnerability in the overlay file system
implementation in the Linux kernel. Unfortunately, that fix introduced
a regression that could incorrectly deny access to overlay files in
some situations. This update fixes the problem.
We apologize for the inconvenience.
Original vulnerability details:
Giuseppe Scrivano discovered that the overlay file system in the Linux
kernel did not properly perform permission checks in some situations. A
local attacker could possibly use this to bypass intended restrictions and
gain read access to restricted files.
USN-4576-1 fixed a vulnerability in the overlay file system
implementation in the Linux kernel. Unfortunately, that fix introduced
a regression that could incorrectly deny access to overlay files in
some situations. This update fixes the problem.
We apologize for the inconvenience.
Original vulnerability details:
Giuseppe Scrivano discovered that the overlay file system in the Linux
kernel did not properly perform permission checks in some situations. A
local attacker could possibly use this to bypass intended restrictions and
gain read access to restricted files.
Update instructions
After a standard system update you need to reboot your computer to make all the necessary changes.
Learn more about how to get the fixes.The problem can be corrected by updating your system to the following package versions:
Reduce your security exposure
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