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

Deferred
AliasesUBUNTU-CVE-2022-50720DEBIAN-CVE-2022-50720
Published 24-12-2025Last modified 11-05-2026

Vulnerability summary

CVE-2022-50720 is a vulnerability in linux with no CVSS score yet. EPSS estimates a 0.24% chance of exploitation in the next 30 days, higher than 15.3% of scored vulnerabilities.

Priority
Insufficient evidence

No CVSS vector published; no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
Not scored
010
No CVSS score recorded
EPSS score
0.24%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 2
RHSA-2024:8613RHSA-2024:9315

Timeline

  1. 24-12-2025
    PublishedVulnerability first disclosed.
  2. 11-05-2026
    Last modifiedVulnerability information updated.

Description

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

CVSS metrics

Risk metrics not yet published.

EPSS trend

Probability

0.24%

Chance of exploitation in the next 30 days

Percentile

15%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.24% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Version check

Known conditions: not stated in public data.

Ubuntu125 products
  • linuxAll versions (No fix recorded)
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded)
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Debian1 product
  • linux< 6.0.3-1
Linux1 product
  • linux≥ fb209bd891645bb87b9618b724f0b4928e0df3de, < 05785ba834f23272f9d23427ae4a80ac505a5296 | ≥ fb209bd891645bb87b9618b724f0b4928e0df3de, < dd1241e00addbf0b95f6cd6ce32152692820657e | ≥ fb209bd891645bb87b9618b724f0b4928e0df3de, < b8d1d163604bd1e600b062fb00de5dc42baa355f | 3.3

3 vendors · 127 products

References

6 links