Vulnerability-Lookup

GHSA-CFCX-RGR2-RQQQ

Vulnerability from github – Published: 2025-10-01 12:30 – Updated: 2026-01-20 21:31

Details

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

x86/fpu: Fix copy_xstate_to_uabi() to copy init states correctly

When an extended state component is not present in fpstate, but in init state, the function copies from init_fpstate via copy_feature().

But, dynamic states are not present in init_fpstate because of all-zeros init states. Then retrieving them from init_fpstate will explode like this:

BUG: kernel NULL pointer dereference, address: 0000000000000000 ... RIP: 0010:memcpy_erms+0x6/0x10 ? __copy_xstate_to_uabi_buf+0x381/0x870 fpu_copy_guest_fpstate_to_uabi+0x28/0x80 kvm_arch_vcpu_ioctl+0x14c/0x1460 [kvm] ? __this_cpu_preempt_check+0x13/0x20 ? vmx_vcpu_put+0x2e/0x260 [kvm_intel] kvm_vcpu_ioctl+0xea/0x6b0 [kvm] ? kvm_vcpu_ioctl+0xea/0x6b0 [kvm] ? __fget_light+0xd4/0x130 __x64_sys_ioctl+0xe3/0x910 ? debug_smp_processor_id+0x17/0x20 ? fpregs_assert_state_consistent+0x27/0x50 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Adjust the 'mask' to zero out the userspace buffer for the features that are not available both from fpstate and from init_fpstate.

The dynamic features depend on the compacted XSAVE format. Ensure it is enabled before reading XCOMP_BV in init_fpstate.

Severity

5.5 (Medium)


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

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2022-50425"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-476"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-10-01T12:15:33Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nx86/fpu: Fix copy_xstate_to_uabi() to copy init states correctly\n\nWhen an extended state component is not present in fpstate, but in init\nstate, the function copies from init_fpstate via copy_feature().\n\nBut, dynamic states are not present in init_fpstate because of all-zeros\ninit states. Then retrieving them from init_fpstate will explode like this:\n\n BUG: kernel NULL pointer dereference, address: 0000000000000000\n ...\n RIP: 0010:memcpy_erms+0x6/0x10\n  ? __copy_xstate_to_uabi_buf+0x381/0x870\n  fpu_copy_guest_fpstate_to_uabi+0x28/0x80\n  kvm_arch_vcpu_ioctl+0x14c/0x1460 [kvm]\n  ? __this_cpu_preempt_check+0x13/0x20\n  ? vmx_vcpu_put+0x2e/0x260 [kvm_intel]\n  kvm_vcpu_ioctl+0xea/0x6b0 [kvm]\n  ? kvm_vcpu_ioctl+0xea/0x6b0 [kvm]\n  ? __fget_light+0xd4/0x130\n  __x64_sys_ioctl+0xe3/0x910\n  ? debug_smp_processor_id+0x17/0x20\n  ? fpregs_assert_state_consistent+0x27/0x50\n  do_syscall_64+0x3f/0x90\n  entry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nAdjust the \u0027mask\u0027 to zero out the userspace buffer for the features that\nare not available both from fpstate and from init_fpstate.\n\nThe dynamic features depend on the compacted XSAVE format. Ensure it is\nenabled before reading XCOMP_BV in init_fpstate.",
  "id": "GHSA-cfcx-rgr2-rqqq",
  "modified": "2026-01-20T21:31:30Z",
  "published": "2025-10-01T12:30:27Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2022-50425"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/471f0aa7fa64e23766a1473b32d9ec3f0718895a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6ff29642fd28965a8f8d6d326ac91bf6075f3113"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2022-50425 (GCVE-0-2022-50425)

Vulnerability from cvelistv5 – Published: 2025-10-01 11:42 – Updated: 2026-05-11 19:19

Title

x86/fpu: Fix copy_xstate_to_uabi() to copy init states correctly

Summary

In the Linux kernel, the following vulnerability has been resolved: x86/fpu: Fix copy_xstate_to_uabi() to copy init states correctly When an extended state component is not present in fpstate, but in init state, the function copies from init_fpstate via copy_feature(). But, dynamic states are not present in init_fpstate because of all-zeros init states. Then retrieving them from init_fpstate will explode like this: BUG: kernel NULL pointer dereference, address: 0000000000000000 ... RIP: 0010:memcpy_erms+0x6/0x10 ? __copy_xstate_to_uabi_buf+0x381/0x870 fpu_copy_guest_fpstate_to_uabi+0x28/0x80 kvm_arch_vcpu_ioctl+0x14c/0x1460 [kvm] ? __this_cpu_preempt_check+0x13/0x20 ? vmx_vcpu_put+0x2e/0x260 [kvm_intel] kvm_vcpu_ioctl+0xea/0x6b0 [kvm] ? kvm_vcpu_ioctl+0xea/0x6b0 [kvm] ? __fget_light+0xd4/0x130 __x64_sys_ioctl+0xe3/0x910 ? debug_smp_processor_id+0x17/0x20 ? fpregs_assert_state_consistent+0x27/0x50 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd Adjust the 'mask' to zero out the userspace buffer for the features that are not available both from fpstate and from init_fpstate. The dynamic features depend on the compacted XSAVE format. Ensure it is enabled before reading XCOMP_BV in init_fpstate.

Severity

No CVSS data available.

Assigner

Linux mitre root

References

2 references

URL	Tags
https://git.kernel.org/stable/c/6ff29642fd28965a8…
https://git.kernel.org/stable/c/471f0aa7fa64e2376…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 2308ee57d93d896618dd65c996429c9d3e469fe0 , < 6ff29642fd28965a8f8d6d326ac91bf6075f3113 (git) Affected: 2308ee57d93d896618dd65c996429c9d3e469fe0 , < 471f0aa7fa64e23766a1473b32d9ec3f0718895a (git)
Linux	Linux	Affected: 5.16 Unaffected: 0 , < 5.16 (semver) Unaffected: 6.0.7 , ≤ 6.0.* (semver) Unaffected: 6.1 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "arch/x86/kernel/fpu/xstate.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "6ff29642fd28965a8f8d6d326ac91bf6075f3113",
              "status": "affected",
              "version": "2308ee57d93d896618dd65c996429c9d3e469fe0",
              "versionType": "git"
            },
            {
              "lessThan": "471f0aa7fa64e23766a1473b32d9ec3f0718895a",
              "status": "affected",
              "version": "2308ee57d93d896618dd65c996429c9d3e469fe0",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "arch/x86/kernel/fpu/xstate.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.16"
            },
            {
              "lessThan": "5.16",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.0.*",
              "status": "unaffected",
              "version": "6.0.7",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.0.7",
                  "versionStartIncluding": "5.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1",
                  "versionStartIncluding": "5.16",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nx86/fpu: Fix copy_xstate_to_uabi() to copy init states correctly\n\nWhen an extended state component is not present in fpstate, but in init\nstate, the function copies from init_fpstate via copy_feature().\n\nBut, dynamic states are not present in init_fpstate because of all-zeros\ninit states. Then retrieving them from init_fpstate will explode like this:\n\n BUG: kernel NULL pointer dereference, address: 0000000000000000\n ...\n RIP: 0010:memcpy_erms+0x6/0x10\n  ? __copy_xstate_to_uabi_buf+0x381/0x870\n  fpu_copy_guest_fpstate_to_uabi+0x28/0x80\n  kvm_arch_vcpu_ioctl+0x14c/0x1460 [kvm]\n  ? __this_cpu_preempt_check+0x13/0x20\n  ? vmx_vcpu_put+0x2e/0x260 [kvm_intel]\n  kvm_vcpu_ioctl+0xea/0x6b0 [kvm]\n  ? kvm_vcpu_ioctl+0xea/0x6b0 [kvm]\n  ? __fget_light+0xd4/0x130\n  __x64_sys_ioctl+0xe3/0x910\n  ? debug_smp_processor_id+0x17/0x20\n  ? fpregs_assert_state_consistent+0x27/0x50\n  do_syscall_64+0x3f/0x90\n  entry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nAdjust the \u0027mask\u0027 to zero out the userspace buffer for the features that\nare not available both from fpstate and from init_fpstate.\n\nThe dynamic features depend on the compacted XSAVE format. Ensure it is\nenabled before reading XCOMP_BV in init_fpstate."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-11T19:19:14.875Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/6ff29642fd28965a8f8d6d326ac91bf6075f3113"
        },
        {
          "url": "https://git.kernel.org/stable/c/471f0aa7fa64e23766a1473b32d9ec3f0718895a"
        }
      ],
      "title": "x86/fpu: Fix copy_xstate_to_uabi() to copy init states correctly",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2022-50425",
    "datePublished": "2025-10-01T11:42:04.776Z",
    "dateReserved": "2025-09-17T14:53:07.004Z",
    "dateUpdated": "2026-05-11T19:19:14.875Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

Detection rules are retrieved from Rulezet.

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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.