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. ]
Advisories
Source ID Title
EUVD EUVD EUVD-2025-12892 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. ]
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Mon, 10 Nov 2025 21:30:00 +0000

Type Values Removed Values Added
Weaknesses NVD-CWE-noinfo
CPEs 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:*:*:*:*:*:*
Metrics cvssV3_1

{'score': 7.1, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H'}

cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}


Sat, 21 Jun 2025 02:45:00 +0000

Type Values Removed Values Added
Metrics cvssV3_1

{'score': 7.0, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}

cvssV3_1

{'score': 7.1, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H'}


Sat, 07 Jun 2025 03:00:00 +0000

Type Values Removed Values Added
Metrics cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

cvssV3_1

{'score': 7.0, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}


Fri, 02 May 2025 14:00:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Moderate


Thu, 01 May 2025 14:30:00 +0000

Type Values Removed Values Added
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. ]
Title x86/tdx: Panic on bad configs that #VE on "private" memory access
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-05-04T08:47:48.152Z

Reserved: 2025-05-01T14:05:17.241Z

Link: CVE-2022-49886

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Analyzed

Published: 2025-05-01T15:16:13.590

Modified: 2025-11-10T21:19:04.303

Link: CVE-2022-49886

cve-icon Redhat

Severity : Moderate

Publid Date: 2025-05-01T00:00:00Z

Links: CVE-2022-49886 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2025-06-24T09:51:39Z