CVE-2022-49886
CVE-2022-49886 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.
Key facts
- Severity: Medium (CVSS 3.x base score 5.5)
- EPSS exploit prediction: 0% (4th percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2025-12892
- Affected product: Linux Linux Kernel
- Published:
- Last modified:
Description
In the Linux kernel, the following vulnerability has been resolved: x86/tdx: Panic on bad configs that #VE on "private" memory access All normal kernel memory is "TDX private memory". This includes everything from kernel stacks to kernel text. Handling exceptions on arbitrary accesses to kernel memory is essentially impossible because they can happen in horribly nasty places like kernel entry/exit. But, TDX hardware can theoretically _deliver_ a virtualization exception (#VE) on any access to private memory. But, it's not as bad as it sounds. TDX can be configured to never deliver these exceptions on private memory with a "TD attribute" called ATTR_SEPT_VE_DISABLE. The guest has no way to *set* this attribute, but it can check it. Ensure ATTR_SEPT_VE_DISABLE is set in early boot. panic() if it is unset. There is no sane way for Linux to run with this attribute clear so a panic() is appropriate. There's small window during boot before the check where kernel has an early #VE handler. But the handler is only for port I/O and will also panic() as soon as it sees any other #VE, such as a one generated by a private memory access. [ dhansen: Rewrite changelog and rebase on new tdx_parse_tdinfo(). Add Kirill's tested-by because I made changes since he wrote this. ]
Frequently asked questions
- What is CVE-2022-49886?
- In the Linux kernel, the following vulnerability has been resolved: x86/tdx: Panic on bad configs that #VE on "private" memory access All normal kernel memory is "TDX private memory". This includes everything from kernel stacks to kernel text. Handling exceptions on arbitrary accesses to kernel memory is essentially impossible because they can happen in horribly nasty places like kernel entry/exit. But, TDX hardware can theoretically _deliver_ a virtualization exception (#VE) on any access to private memory. But, it's not as bad as it sounds. TDX can be configured to never deliver these exceptions on private memory with a "TD attribute" called ATTR_SEPT_VE_DISABLE. The guest has no way to *set* this attribute, but it can check it. Ensure ATTR_SEPT_VE_DISABLE is set in early boot. panic() if it is unset. There is no sane way for Linux to run with this attribute clear so a panic() is appropriate. There's small window during boot before the check where kernel has an early #VE handler. But the handler is only for port I/O and will also panic() as soon as it sees any other #VE, such as a one generated by a private memory access. [ dhansen: Rewrite changelog and rebase on new tdx_parse_tdinfo(). Add Kirill's tested-by because I made changes since he wrote this. ]
- How severe is CVE-2022-49886?
- CVE-2022-49886 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2022-49886 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (4th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2022-49886?
- CVE-2022-49886 primarily affects Linux Linux Kernel. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2022-49886?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- Does CVE-2022-49886 have an EU (EUVD) identifier?
- Yes. CVE-2022-49886 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-12892.
- When was CVE-2022-49886 published?
- CVE-2022-49886 was published on 2025-05-01 and last updated on 2026-06-17.
References
- https://git.kernel.org/stable/c/373e715e31bf4e0f129befe87613a278fac228d3
- https://git.kernel.org/stable/c/895c168c8f78079f21ad50fead7593ffa352f795
Affected products (4)
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:6.1:rc1:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:6.1:rc2:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:6.1:rc3:*:*:*:*:*:*
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