CVE-2021-22566

Incorrect mapping of Executable bits in Fuchsia Kernel

Description

An incorrect setting of UXN bits within mmu_flags_to_s1_pte_attr lead to privileged executable pages being mapped as executable from an unprivileged context. This can be leveraged by an attacker to bypass executability restrictions of kernel-mode pages from user-mode. An incorrect setting of PXN bits within mmu_flags_to_s1_pte_attr lead to unprivileged executable pages being mapped as executable from a privileged context. This can be leveraged by an attacker to bypass executability restrictions of user-mode pages from kernel-mode. Typically this allows a potential attacker to circumvent a mitigation, making exploitation of potential kernel-mode vulnerabilities easier. We recommend updating kernel beyond commit 7d731b4e9599088ac3073956933559da7bca6a00 and rebuilding.

Categories

5.1
CVSS
Severity: Medium
CVSS 4.0 •
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.01%
Third-Party Advisory googlesource.com
Affected: Google LLC Fuchsia
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-22566?
CVE-2021-22566 has been scored as a medium severity vulnerability.
How to fix CVE-2021-22566?
To fix CVE-2021-22566, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-22566 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-22566 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-22566?
CVE-2021-22566 affects Google LLC Fuchsia.
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