Vulnerability-Lookup

GHSA-M99H-2HM4-Q649

Vulnerability from github – Published: 2024-02-28 09:30 – Updated: 2025-01-08 18:30

Details

In the Linux kernel, the following vulnerability has been resolved:

KVM: VMX: Disable preemption when probing user return MSRs

Disable preemption when probing a user return MSR via RDSMR/WRMSR. If the MSR holds a different value per logical CPU, the WRMSR could corrupt the host's value if KVM is preempted between the RDMSR and WRMSR, and then rescheduled on a different CPU.

Opportunistically land the helper in common x86, SVM will use the helper in a future commit.

Severity

5.5 (Medium)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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{
  "affected": [],
  "aliases": [
    "CVE-2021-46977"
  ],
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    "cwe_ids": [],
    "github_reviewed": false,
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  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: VMX: Disable preemption when probing user return MSRs\n\nDisable preemption when probing a user return MSR via RDSMR/WRMSR.  If\nthe MSR holds a different value per logical CPU, the WRMSR could corrupt\nthe host\u0027s value if KVM is preempted between the RDMSR and WRMSR, and\nthen rescheduled on a different CPU.\n\nOpportunistically land the helper in common x86, SVM will use the helper\nin a future commit.",
  "id": "GHSA-m99h-2hm4-q649",
  "modified": "2025-01-08T18:30:40Z",
  "published": "2024-02-28T09:30:36Z",
  "references": [
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      "type": "CVSS_V3"
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}

CVE-2021-46977 (GCVE-0-2021-46977)

Vulnerability from cvelistv5 – Published: 2024-02-28 08:13 – Updated: 2026-08-05 08:45

Title

KVM: VMX: Disable preemption when probing user return MSRs

Summary

In the Linux kernel, the following vulnerability has been resolved: KVM: VMX: Disable preemption when probing user return MSRs Disable preemption when probing a user return MSR via RDSMR/WRMSR. If the MSR holds a different value per logical CPU, the WRMSR could corrupt the host's value if KVM is preempted between the RDMSR and WRMSR, and then rescheduled on a different CPU. Opportunistically land the helper in common x86, SVM will use the helper in a future commit.

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2024-06-21 16:27 UTC

Assigner

Linux CNA under the mitre root

CNA scorecard D 53/100 over 6854 records in the last 180 days details

References

4 references

URL	Tags
https://git.kernel.org/stable/c/31f29749ee970c251…
https://git.kernel.org/stable/c/5adcdeb57007ccf8a…
https://git.kernel.org/stable/c/e3ea1895df719c4ef…
https://git.kernel.org/stable/c/5104d7ffcf2474993…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 4be5341026246870818e28b53202b001426a5aec , < 31f29749ee970c251b3a7e5b914108425940d089 (git) Affected: 4be5341026246870818e28b53202b001426a5aec , < 5adcdeb57007ccf8ab7ac20bf787ffb6fafb1a94 (git) Affected: 4be5341026246870818e28b53202b001426a5aec , < e3ea1895df719c4ef87862501bb10d95f4177bed (git) Affected: 4be5341026246870818e28b53202b001426a5aec , < 5104d7ffcf24749939bea7fdb5378d186473f890 (git)
Linux	Linux	Affected: 5.5 Unaffected: 0 , < 5.5 (semver) Unaffected: 5.10.38 , ≤ 5.10.* (semver) Unaffected: 5.11.22 , ≤ 5.11.* (semver) Unaffected: 5.12.5 , ≤ 5.12.* (semver) Unaffected: 5.13 , ≤ * (original_commit_for_fix)

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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