CVE-2022-50720 | x86/apic: Don't disable x2APIC if locked

In the Linux kernel, the following vulnerability has been resolved: x86/apic: Don't disable x2APIC if locked The APIC supports two modes, legacy APIC (or xAPIC), and Extended APIC (or x2APIC). X2APIC mode is mostly compatible with legacy APIC, but it disables the memory-mapped APIC interface in favor of one that uses MSRs. The APIC mode is controlled by the EXT bit in the APIC MSR. The MMIO/xAPIC interface has some problems, most notably the APIC LEAK [1]. This bug allows an attacker to use the APIC MMIO interface to extract data from the SGX enclave. Introduce support for a new feature that will allow the BIOS to lock the APIC in x2APIC mode. If the APIC is locked in x2APIC mode and the kernel tries to disable the APIC or revert to legacy APIC mode a GP fault will occur. Introduce support for a new MSR (IA32_XAPIC_DISABLE_STATUS) and handle the new locked mode when the LEGACY_XAPIC_DISABLED bit is set by preventing the kernel from trying to disable the x2APIC. On platforms with the IA32_XAPIC_DISABLE_STATUS MSR, if SGX or TDX are enabled the LEGACY_XAPIC_DISABLED will be set by the BIOS. If legacy APIC is required, then it SGX and TDX need to be disabled in the BIOS. [1]: https://aepicleak.com/aepicleak.pdf

Published: 2025-12-24 Last update: 2026-04-15 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Conclusion & alert: CVE-2022-50720 is rated Low Risk (3.2/100): low exploitation likelihood (EPSS 0.02%). Mandatory action: Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2022-50720

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-12-25 0.02%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2022-50720

CVSS metrics for this CVE.

No CVSS data in dataset for this CVE.

Weakness enumeration for CVE-2022-50720

OS Trackers for CVE-2022-50720

vendor priority summary link
debian not yet assigned CVE-2022-50720 not yet assigned priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 4, open 1. https://security-tracker.debian.org/tracker/CVE-2022-50720
redhat low https://access.redhat.com/security/cve/CVE-2022-50720
suse medium CVE-2022-50720 severity moderate: SUSE including 25 source package names (cluster-md-kmp-default, dlm-kmp-default, …), 142 product×package rows across 29 product lines (SUSE Linux Enterprise High Availability Extension 15 SP6, SUSE Linux Enterprise High Availability Extension 15 SP7, … (29 product lines)): Known Not Affected 123, Will Not Fix 19. https://www.suse.com/security/cve/CVE-2022-50720/
ubuntu medium CVE-2022-50720 medium priority: Ubuntu including 157 source packages (linux, linux-allwinner-5.19, …), 1405 status rows across 9 suites (bionic, focal, jammy, noble, plucky, questing, trusty, upstream, xenial): DNE 1010, ignored 177, released 83, needed 75, not-affected 60. https://ubuntu.com/security/CVE-2022-50720

Affected software / configurations for CVE-2022-50720

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2022-50720

cvelogic Threat Intelligence