CVE-2022-50720
0.02%V4
2025-12-24
12h22 +00:00
12h22 +00:00
指定 CVE 通知
掌握特定 CVE 的任何變更。
CVE 描述
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.pdfCVE 資訊
EPSS
EPSS 是一種預測漏洞被利用可能性的評分模型。
EPSS 評分
EPSS 模型產生介於 0 到 1（0% 到 100%）之間的概率分數。分數越高，漏洞被利用的概率越大。
EPSS 百分位數
百分位數用於根據 EPSS 分數對 CVE 進行排名。例如，EPSS 評分在第 95 百分位的 CVE 比 95% 的其他 CVE 更有可能被利用。因此，百分位數用於比較某 CVE 的 EPSS 分數與其他 CVE 的相對位置。
