CVE-2021-22566 MEDIUM

CVE-2021-22566: Incorrect mapping of Executable bits in Fuchsia Kernel

Vendor Google Llc
Product Fuchsia
Weakness CWE-275
Published January 18, 2022
Last update August 3, 2024

CVSS base score

5.1/10
Attack vector Local
Attack complexity Low
Privileges required None
User interaction None
Confidentiality
Integrity

CVSS vector

CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

January 18, 2022 CVE published
August 3, 2024 Record updated