Vulnerability-Lookup

FKIE_CVE-2025-21950

Vulnerability from fkie_nvd - Published: 2025-04-01 16:15 - Updated: 2026-06-17 08:44

Severity

7.1 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

Summary

In the Linux kernel, the following vulnerability has been resolved: drivers: virt: acrn: hsm: Use kzalloc to avoid info leak in pmcmd_ioctl In the "pmcmd_ioctl" function, three memory objects allocated by kmalloc are initialized by "hcall_get_cpu_state", which are then copied to user space. The initializer is indeed implemented in "acrn_hypercall2" (arch/x86/include/asm/acrn.h). There is a risk of information leakage due to uninitialized bytes.

References

URL	Tags
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/1b8f7a2caa7f9cdfd135e3f78eb9d7e36fb95083	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/4e15cf870d2c748e45d45ffc4d5b1dc1b7d50120	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/524f29d78c9bdeb49f31f5b0376a07d2fc5cf563	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/819cec1dc47cdeac8f5dd6ba81c1dbee2a68c3bb	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/a4c21b878f0e237f45209a324c903ea7fb05247d	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/d7e5031fe3f161c8eb5e84db1540bc4373ed861b	Patch
af854a3a-2127-422b-91ae-364da2661108	https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html	Third Party Advisory

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	6.14
linux	linux_kernel	6.14
linux	linux_kernel	6.14
linux	linux_kernel	6.14
linux	linux_kernel	6.14
debian	debian_linux	11.0

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/virt/acrn/hsm.c"
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          ],
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            {
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            },
            {
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              "status": "unaffected",
              "version": "6.14",
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            }
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        }
      ],
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    }
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  "configurations": [
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  "cveTags": [],
  "descriptions": [
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      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrivers: virt: acrn: hsm: Use kzalloc to avoid info leak in pmcmd_ioctl\n\nIn the \"pmcmd_ioctl\" function, three memory objects allocated by\nkmalloc are initialized by \"hcall_get_cpu_state\", which are then\ncopied to user space. The initializer is indeed implemented in\n\"acrn_hypercall2\" (arch/x86/include/asm/acrn.h). There is a risk of\ninformation leakage due to uninitialized bytes."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: drivers: virt: acrn: hsm: Usar kzalloc para evitar fugas de informaci\u00f3n en pmcmd_ioctl. En la funci\u00f3n \"pmcmd_ioctl\", tres objetos de memoria asignados por kmalloc se inicializan mediante \"hcall_get_cpu_state\", que posteriormente se copian al espacio de usuario. El inicializador est\u00e1 implementado en \"acrn_hypercall2\" (arch/x86/include/asm/acrn.h). Existe riesgo de fuga de informaci\u00f3n debido a bytes no inicializados."
    }
  ],
  "id": "CVE-2025-21950",
  "lastModified": "2026-06-17T08:44:41.453",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 7.1,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H",
          "version": "3.1"
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        "impactScore": 5.2,
        "source": "nvd@nist.gov",
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  "vulnStatus": "Analyzed",
  "weaknesses": [
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          "value": "NVD-CWE-noinfo"
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      "source": "nvd@nist.gov",
      "type": "Primary"
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  ]
}

CVE-2025-21950 (GCVE-0-2025-21950)

Vulnerability from cvelistv5 – Published: 2025-04-01 15:41 – Updated: 2026-05-11 21:09

Title

drivers: virt: acrn: hsm: Use kzalloc to avoid info leak in pmcmd_ioctl

Summary

Severity

No CVSS data available.

Assigner

Linux mitre root

References

7 references

URL	Tags
https://git.kernel.org/stable/c/4e15cf870d2c748e4…
https://git.kernel.org/stable/c/524f29d78c9bdeb49…
https://git.kernel.org/stable/c/d7e5031fe3f161c8e…
https://git.kernel.org/stable/c/1b8f7a2caa7f9cdfd…
https://git.kernel.org/stable/c/a4c21b878f0e237f4…
https://git.kernel.org/stable/c/819cec1dc47cdeac8…
https://lists.debian.org/debian-lts-announce/2025…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 3d679d5aec648f50e645702929890b9611998a0b , < 4e15cf870d2c748e45d45ffc4d5b1dc1b7d50120 (git) Affected: 3d679d5aec648f50e645702929890b9611998a0b , < 524f29d78c9bdeb49f31f5b0376a07d2fc5cf563 (git) Affected: 3d679d5aec648f50e645702929890b9611998a0b , < d7e5031fe3f161c8eb5e84db1540bc4373ed861b (git) Affected: 3d679d5aec648f50e645702929890b9611998a0b , < 1b8f7a2caa7f9cdfd135e3f78eb9d7e36fb95083 (git) Affected: 3d679d5aec648f50e645702929890b9611998a0b , < a4c21b878f0e237f45209a324c903ea7fb05247d (git) Affected: 3d679d5aec648f50e645702929890b9611998a0b , < 819cec1dc47cdeac8f5dd6ba81c1dbee2a68c3bb (git)
Linux	Linux	Affected: 5.12 Unaffected: 0 , < 5.12 (semver) Unaffected: 5.15.179 , ≤ 5.15.* (semver) Unaffected: 6.1.131 , ≤ 6.1.* (semver) Unaffected: 6.6.83 , ≤ 6.6.* (semver) Unaffected: 6.12.19 , ≤ 6.12.* (semver) Unaffected: 6.13.7 , ≤ 6.13.* (semver) Unaffected: 6.14 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2025-11-03T19:39:51.532Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "url": "https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
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        {
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          "programFiles": [
            "drivers/virt/acrn/hsm.c"
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              "version": "0",
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              "status": "unaffected",
              "version": "6.6.83",
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              "version": "6.12.19",
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              "version": "6.13.7",
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              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.14",
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        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-11T21:09:40.823Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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        },
        {
          "url": "https://git.kernel.org/stable/c/819cec1dc47cdeac8f5dd6ba81c1dbee2a68c3bb"
        }
      ],
      "title": "drivers: virt: acrn: hsm: Use kzalloc to avoid info leak in pmcmd_ioctl",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-21950",
    "datePublished": "2025-04-01T15:41:10.949Z",
    "dateReserved": "2024-12-29T08:45:45.790Z",
    "dateUpdated": "2026-05-11T21:09:40.823Z",
    "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.