CVE-2022-49124
published 2025-02-26CVE-2022-49124: In the Linux kernel, the following vulnerability has been resolved: x86/mce: Work around an erratum on fast string copy instructions A rare kernel panic…
PriorityP421medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.25%
16.6th percentile
In the Linux kernel, the following vulnerability has been resolved:
x86/mce: Work around an erratum on fast string copy instructions
A rare kernel panic scenario can happen when the following conditions
are met due to an erratum on fast string copy instructions:
1) An uncorrected error.
2) That error must be in first cache line of a page.
3) Kernel must execute page_copy from the page immediately before that
page.
The fast string copy instructions ("REP; MOVS*") could consume an
uncorrectable memory error in the cache line _right after_ the desired
region to copy and raise an MCE.
Bit 0 of MSR_IA32_MISC_ENABLE can be cleared to disable fast string
copy and will avoid such spurious machine checks. However, that is less
preferable due to the permanent performance impact. Considering memory
poison is rare, it's desirable to keep fast string copy enabled until an
MCE is seen.
Intel has confirmed the following:
1. The CPU erratum of fast string copy only applies to Skylake,
Cascade Lake and Cooper Lake generations.
Directly return from the MCE handler:
2. Will result in complete execution of the "REP; MOVS*" with no data
loss or corruption.
3. Will not result in another MCE firing on the next poisoned cache line
due to "REP; MOVS*".
4. Will resume execution from a correct point in code.
5. Will result in the same instruction that triggered the MCE firing a
second MCE immediately for any other software recoverable data fetch
errors.
6. Is not safe without disabling the fast string copy, as the next fast
string copy of the same buffer on the same CPU would result in a PANIC
MCE.
This should mitigate the erratum completely with the only caveat that
the fast string copy is disabled on the affected hyper thread thus
performance degradation.
This is still better than the OS crashing on MCEs raised on an
irrelevant process due to "REP; MOVS*' accesses in a kernel context,
e.g., copy_page.
Injected errors on 1st cache line of 8 anonymous pages of process
'proc1' and o
Affected
11 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 5.17.3-1 (bookworm) | linux 5.17.3-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | >= 27fbe5b28a2ffef171c6005f304ea4f80fcdcc01 < ba37c73be3d5632f6fb9fa20b250ce45560ca85d | ba37c73be3d5632f6fb9fa20b250ce45560ca85d |
| linux | linux | >= 27fbe5b28a2ffef171c6005f304ea4f80fcdcc01 < 8ca97812c3c830573f965a07bbd84223e8c5f5bd | 8ca97812c3c830573f965a07bbd84223e8c5f5bd |
| linux | linux_kernel | < 5.17.3 | 5.17.3 |
| linux | linux_kernel | >= 0 < 5.17.3-1 | 5.17.3-1 |
| linux | linux_kernel | >= 0 < 5.17.3-1 | 5.17.3-1 |
| linux | linux_kernel | >= 0 < 5.17.3-1 | 5.17.3-1 |
| msrc | cbl2_kernel_5.15.186.1-1_on_cbl_mariner_2.0 | — | — |
| msrc | cbl2_kernel_5.15.200.1-1_on_cbl_mariner_2.0 | — | — |
| msrc | cbl2_kernel_5.15.202.1-1_on_cbl_mariner_2.0 | — | — |
CVSS provenance
nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_msrc5.5MEDIUM
vendor_redhat5.5MEDIUM
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Red Hat
kernel: x86/mce: Work around an erratum on fast string copy instructions
vendor_redhat·2025-02-26·CVSS 5.5
CVE-2022-49124 [MEDIUM] CWE-99 kernel: x86/mce: Work around an erratum on fast string copy instructions
kernel: x86/mce: Work around an erratum on fast string copy instructions
In the Linux kernel, the following vulnerability has been resolved:
x86/mce: Work around an erratum on fast string copy instructions
A rare kernel panic scenario can happen when the following conditions
are met due to an erratum on fast string copy instructions:
1) An uncorrected error.
2) That error must be in first cache line of a page.
3) Kernel must execute page_copy from the page immediately before that
page.
The fast string copy instructions ("REP; MOVS*") could consume an
uncorrectable memory error in the cache line _right after_ the desired
region to copy and raise an MCE.
Bit 0 of MSR_IA32_MISC_ENABLE can be cleared to disable fast string
copy and will avoid such spurious machine checks. However, that is les
Microsoft
x86/mce: Work around an erratum on fast string copy instructions
vendor_msrc·2025-02-11·CVSS 5.5
CVE-2022-49124 [MEDIUM] x86/mce: Work around an erratum on fast string copy instructions
x86/mce: Work around an erratum on fast string copy instructions
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Mariner: Mariner
Linux: Linux
Customer Action Required: Yes
Debian
CVE-2022-49124: linux - In the Linux kernel, the following vulnerability has been resolved: x86/mce: Wo...
vendor_debian·2022·CVSS 5.5
CVE-2022-49124 [MEDIUM] CVE-2022-49124: linux - In the Linux kernel, the following vulnerability has been resolved: x86/mce: Wo...
In the Linux kernel, the following vulnerability has been resolved: x86/mce: Work around an erratum on fast string copy instructions A rare kernel panic scenario can happen when the following conditions are met due to an erratum on fast string copy instructions: 1) An uncorrected error. 2) That error must be in first cache line of a page. 3) Kernel must execute page_copy from the page immediately before that page. The fast string copy instructions ("REP; MOVS*") could consume an uncorrectable memory error in the cache line _right after_ the desired region to copy and raise an MCE. Bit 0 of MSR_IA32_MISC_ENABLE can be cleared to disable fast string copy and will avoid such spurious machine checks. However, that is less preferable due to the permanent performance impact. Considering memory p
GHSA
GHSA-5ghh-886p-hpp6: In the Linux kernel, the following vulnerability has been resolved:
x86/mce: Work around an erratum on fast string copy instructions
A rare kernel p
ghsa_unreviewed·2025-10-15
CVE-2022-49124 [MEDIUM] GHSA-5ghh-886p-hpp6: In the Linux kernel, the following vulnerability has been resolved:
x86/mce: Work around an erratum on fast string copy instructions
A rare kernel p
In the Linux kernel, the following vulnerability has been resolved:
x86/mce: Work around an erratum on fast string copy instructions
A rare kernel panic scenario can happen when the following conditions
are met due to an erratum on fast string copy instructions:
1) An uncorrected error.
2) That error must be in first cache line of a page.
3) Kernel must execute page_copy from the page immediately before that
page.
The fast string copy instructions ("REP; MOVS*") could consume an
uncorrectable memory error in the cache line _right after_ the desired
region to copy and raise an MCE.
Bit 0 of MSR_IA32_MISC_ENABLE can be cleared to disable fast string
copy and will avoid such spurious machine checks. However, that is less
preferable due to the permanent performance impact. Considering mem
OSV
CVE-2022-49124: In the Linux kernel, the following vulnerability has been resolved: x86/mce: Work around an erratum on fast string copy instructions A rare kernel pan
osv·2025-02-26·CVSS 5.5
CVE-2022-49124 [MEDIUM] CVE-2022-49124: In the Linux kernel, the following vulnerability has been resolved: x86/mce: Work around an erratum on fast string copy instructions A rare kernel pan
In the Linux kernel, the following vulnerability has been resolved: x86/mce: Work around an erratum on fast string copy instructions A rare kernel panic scenario can happen when the following conditions are met due to an erratum on fast string copy instructions: 1) An uncorrected error. 2) That error must be in first cache line of a page. 3) Kernel must execute page_copy from the page immediately before that page. The fast string copy instructions ("REP; MOVS*") could consume an uncorrectable memory error in the cache line _right after_ the desired region to copy and raise an MCE. Bit 0 of MSR_IA32_MISC_ENABLE can be cleared to disable fast string copy and will avoid such spurious machine checks. However, that is less preferable due to the permanent performance impact. Considering memory p
No detection rules found.
No public exploits indexed.
2025-02-26
Published