CVE-2023-52481 arm64: errata: Add Cortex-A520 speculative unprivileged load workaround
A speculative execution flaw in the Linux kernel on Cortex-A520 allows attackers to leak privileged data via cache side channels.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-52481?
CVE-2023-52481 is a medium-severity vulnerability in Linux kernel, published on 29 Feb 2024. An attacker needs administrator access to exploit it, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
arm64: errata: Add Cortex-A520 speculative unprivileged load workaround
Implement the workaround for ARM Cortex-A520 erratum 2966298. On an affected Cortex-A520 core, a speculatively executed unprivileged load might leak data from a privileged load via a cache side channel. The issue only exists for loads within a translation regime with the same translation (e.g. same ASID and VMID). Therefore, the issue only affects the return to EL0.
The workaround is to execute a TLBI before returning to EL0 after all loads of privileged data. A non-shareable TLBI to any address is sufficient.
The workaround isn't necessary if page table isolation (KPTI) is enabled, but for simplicity it will be. Page table isolation should normally be disabled for Cortex-A520 as it supports the CSV3 feature and the E0PD feature (used when KASLR is enabled).
Which versions are affected by CVE-2023-52481?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2023-52481?
Apply the vendor's patch.
Is CVE-2023-52481 being exploited?
There is no known exploitation of CVE-2023-52481 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-59471, BELL-CVE-2023-52481, DEBIAN-CVE-2023-52481, GHSA-3qpr-v3fc-q5q5, ROOT-OS-DEBIAN-11-CVE-2023-52481, ROOT-OS-UBUNTU-2204-CVE-2023-52481 and 1 more.