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CVE-2025-68195 (GCVE-0-2025-68195)

Vulnerability from cvelistv5 – Published: 2025-12-16 13:43 – Updated: 2026-08-05 12:10
VLAI
Title
x86/CPU/AMD: Add missing terminator for zen5_rdseed_microcode
Summary
In the Linux kernel, the following vulnerability has been resolved: x86/CPU/AMD: Add missing terminator for zen5_rdseed_microcode Running x86_match_min_microcode_rev() on a Zen5 CPU trips up KASAN for an out of bounds access.
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 36ff93e66d0efc46e39fab536a9feec968daa766 , < 4c6b56a76478bd1ab609827c571905386c11d308 (git)
Affected: 607b9fb2ce248cc5b633c5949e0153838992c152 , < f1fdffe0afea02ba783acfe815b6a60e7180df40 (git)
Affected: e980de2ff109dacb6d9d3a77f01b27c467115ecb (git)
Affected: 6.12.58 , < 6.13 (semver)
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Show details on NVD website

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "arch/x86/kernel/cpu/amd.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "4c6b56a76478bd1ab609827c571905386c11d308",
              "status": "affected",
              "version": "36ff93e66d0efc46e39fab536a9feec968daa766",
              "versionType": "git"
            },
            {
              "lessThan": "f1fdffe0afea02ba783acfe815b6a60e7180df40",
              "status": "affected",
              "version": "607b9fb2ce248cc5b633c5949e0153838992c152",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "e980de2ff109dacb6d9d3a77f01b27c467115ecb",
              "versionType": "git"
            },
            {
              "lessThan": "6.13",
              "status": "affected",
              "version": "6.12.58",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "arch/x86/kernel/cpu/amd.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux"
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "6.12.58",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nx86/CPU/AMD: Add missing terminator for zen5_rdseed_microcode\n\nRunning x86_match_min_microcode_rev() on a Zen5 CPU trips up KASAN for an out\nof bounds access."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.1,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The vulnerable lookup is reached through local CPU boot or secondary-CPU bring-up; no network packets or remotely supplied data reach this path.\nAC:L - On an affected Zen5 CPU not matched by the two valid entries, the table scan deterministically crosses the array boundary without requiring a race, timing window, or other attacker-independent condition.\nPR:L - The lookup contains no capability or authentication check and executes automatically during CPU initialization; conservatively, a basic local foothold is sufficient rather than init-namespace root.\nUI:N - The invalid lookup occurs during CPU initialization without requiring a victim to open a file, mount media, or perform another action.\nS:U - The impact remains within the affected kernel and host; this is not a guest-to-host escape or another security-authority boundary crossing.\nC:H - The missing sentinel permits a source-unbounded read into adjacent kernel memory; the closest prior AMD missing-terminator case was likewise classified as CWE-125 with C:H ([CVE-2024-56721](https://nvd.nist.gov/vuln/detail/CVE-2024-56721)).\nI:N - The overrun is read-only: no out-of-bounds-derived value becomes a write address or control-flow target, and AMD separately tracks the underlying RDSEED entropy defect as CVE-2025-62626 ([AMD-SB-7055](https://www.amd.com/en/resources/product-security/bul letin/amd-sb-7055.html)).\nA:H - KASAN detects the invalid access, and panic_on_warn or kasan.fault=panic converts the report into a kernel panic during boot or CPU bring-up, making the system unavailable."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T12:10:10.646Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/4c6b56a76478bd1ab609827c571905386c11d308"
        },
        {
          "url": "https://git.kernel.org/stable/c/f1fdffe0afea02ba783acfe815b6a60e7180df40"
        }
      ],
      "title": "x86/CPU/AMD: Add missing terminator for zen5_rdseed_microcode",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-68195",
    "datePublished": "2025-12-16T13:43:21.855Z",
    "dateReserved": "2025-12-16T13:41:40.253Z",
    "dateUpdated": "2026-08-05T12:10:10.646Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2025-68195",
      "date": "2026-09-19",
      "epss": "0.0014",
      "percentile": "0.03767"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
                  "arch/x86/kernel/cpu/amd.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "lessThan": "4c6b56a76478bd1ab609827c571905386c11d308",
                    "status": "affected",
                    "version": "36ff93e66d0efc46e39fab536a9feec968daa766",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "f1fdffe0afea02ba783acfe815b6a60e7180df40",
                    "status": "affected",
                    "version": "607b9fb2ce248cc5b633c5949e0153838992c152",
                    "versionType": "git"
                  },
                  {
                    "status": "affected",
                    "version": "e980de2ff109dacb6d9d3a77f01b27c467115ecb",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "6.13",
                    "status": "affected",
                    "version": "6.12.58",
                    "versionType": "semver"
                  }
                ]
              },
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
                  "arch/x86/kernel/cpu/amd.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux"
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nx86/CPU/AMD: Add missing terminator for zen5_rdseed_microcode\n\nRunning x86_match_min_microcode_rev() on a Zen5 CPU trips up KASAN for an out\nof bounds access."
          }
        ],
        "id": "CVE-2025-68195",
        "lastModified": "2026-07-30T06:24:33.117",
        "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"
              },
              "exploitabilityScore": 1.8,
              "impactScore": 5.2,
              "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
              "type": "Secondary"
            }
          ]
        },
        "published": "2025-12-16T14:15:52.263",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/4c6b56a76478bd1ab609827c571905386c11d308"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/f1fdffe0afea02ba783acfe815b6a60e7180df40"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Deferred"
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-08-13T17:54:55+00:00",
      "cve": "CVE-2025-68195",
      "id": "CVE-2025-68195",
      "initial_release_date": "2025-12-16T00:00:00+00:00",
      "product_status:known_not_affected": "274",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: Linux kernel: Denial of service via out-of-bounds memory access in AMD Zen5 microcode handling",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-68195.json",
      "version": "3"
    }
  }
}



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