GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

CVE-2022-49955 (GCVE-0-2022-49955)

Vulnerability from cvelistv5 – Published: 2025-06-18 11:00 – Updated: 2026-05-23 15:23
VLAI
Title
powerpc/rtas: Fix RTAS MSR[HV] handling for Cell
Summary
In the Linux kernel, the following vulnerability has been resolved: powerpc/rtas: Fix RTAS MSR[HV] handling for Cell The semi-recent changes to MSR handling when entering RTAS (firmware) cause crashes on IBM Cell machines. An example trace: kernel tried to execute user page (2fff01a8) - exploit attempt? (uid: 0) BUG: Unable to handle kernel instruction fetch Faulting instruction address: 0x2fff01a8 Oops: Kernel access of bad area, sig: 11 [#1] BE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=4 NUMA Cell Modules linked in: CPU: 0 PID: 0 Comm: swapper/0 Tainted: G W 6.0.0-rc2-00433-gede0a8d3307a #207 NIP: 000000002fff01a8 LR: 0000000000032608 CTR: 0000000000000000 REGS: c0000000015236b0 TRAP: 0400 Tainted: G W (6.0.0-rc2-00433-gede0a8d3307a) MSR: 0000000008001002 <ME,RI> CR: 00000000 XER: 20000000 ... NIP 0x2fff01a8 LR 0x32608 Call Trace: 0xc00000000143c5f8 (unreliable) .rtas_call+0x224/0x320 .rtas_get_boot_time+0x70/0x150 .read_persistent_clock64+0x114/0x140 .read_persistent_wall_and_boot_offset+0x24/0x80 .timekeeping_init+0x40/0x29c .start_kernel+0x674/0x8f0 start_here_common+0x1c/0x50 Unlike PAPR platforms where RTAS is only used in guests, on the IBM Cell machines Linux runs with MSR[HV] set but also uses RTAS, provided by SLOF. Fix it by copying the MSR[HV] bit from the MSR value we've just read using mfmsr into the value used for RTAS. It seems like we could also fix it using an #ifdef CELL to set MSR[HV], but that doesn't work because it's possible to build a single kernel image that runs on both Cell native and pseries.
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: b6b1c3ce06ca438eb24e0f45bf0e63ecad0369f5 , < 8b08d4f97233d8e58fff2fd9d5f86397a49733c5 (git)
Affected: b6b1c3ce06ca438eb24e0f45bf0e63ecad0369f5 , < 91926d8b7e71aaf5f84f0cf208fc5a8b7a761050 (git)
Affected: 5ca40fcf0da0ce2b5bc44e7d8b036535955f2e3d (git)
Affected: 5f4367448f6817c8a0e94dc9736ed84fa8eee4a3 (git)
Affected: c9c41f0273826a13ac93124e66a4ff45df281ba0 (git)
Affected: 5.15.46 , < 5.16 (semver)
Affected: 5.17.14 , < 5.18 (semver)
Affected: 5.18.3 , < 5.19 (semver)
guessed Create a notification for this product.
Linux Linux Affected: 5.19
Unaffected: 0 , < 5.19 (semver)
Unaffected: 5.19.8 , ≤ 5.19.* (semver)
Unaffected: 6.0 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "arch/powerpc/kernel/rtas_entry.S"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "8b08d4f97233d8e58fff2fd9d5f86397a49733c5",
              "status": "affected",
              "version": "b6b1c3ce06ca438eb24e0f45bf0e63ecad0369f5",
              "versionType": "git"
            },
            {
              "lessThan": "91926d8b7e71aaf5f84f0cf208fc5a8b7a761050",
              "status": "affected",
              "version": "b6b1c3ce06ca438eb24e0f45bf0e63ecad0369f5",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "5ca40fcf0da0ce2b5bc44e7d8b036535955f2e3d",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "5f4367448f6817c8a0e94dc9736ed84fa8eee4a3",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "c9c41f0273826a13ac93124e66a4ff45df281ba0",
              "versionType": "git"
            },
            {
              "lessThan": "5.16",
              "status": "affected",
              "version": "5.15.46",
              "versionType": "semver"
            },
            {
              "lessThan": "5.18",
              "status": "affected",
              "version": "5.17.14",
              "versionType": "semver"
            },
            {
              "lessThan": "5.19",
              "status": "affected",
              "version": "5.18.3",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "arch/powerpc/kernel/rtas_entry.S"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.19"
            },
            {
              "lessThan": "5.19",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.19.*",
              "status": "unaffected",
              "version": "5.19.8",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.0",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.19.8",
                  "versionStartIncluding": "5.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.0",
                  "versionStartIncluding": "5.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "5.15.46",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "5.17.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "5.18.3",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\npowerpc/rtas: Fix RTAS MSR[HV] handling for Cell\n\nThe semi-recent changes to MSR handling when entering RTAS (firmware)\ncause crashes on IBM Cell machines. An example trace:\n\n  kernel tried to execute user page (2fff01a8) - exploit attempt? (uid: 0)\n  BUG: Unable to handle kernel instruction fetch\n  Faulting instruction address: 0x2fff01a8\n  Oops: Kernel access of bad area, sig: 11 [#1]\n  BE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=4 NUMA Cell\n  Modules linked in:\n  CPU: 0 PID: 0 Comm: swapper/0 Tainted: G        W          6.0.0-rc2-00433-gede0a8d3307a #207\n  NIP:  000000002fff01a8 LR: 0000000000032608 CTR: 0000000000000000\n  REGS: c0000000015236b0 TRAP: 0400   Tainted: G        W           (6.0.0-rc2-00433-gede0a8d3307a)\n  MSR:  0000000008001002 \u003cME,RI\u003e  CR: 00000000  XER: 20000000\n  ...\n  NIP 0x2fff01a8\n  LR  0x32608\n  Call Trace:\n    0xc00000000143c5f8 (unreliable)\n    .rtas_call+0x224/0x320\n    .rtas_get_boot_time+0x70/0x150\n    .read_persistent_clock64+0x114/0x140\n    .read_persistent_wall_and_boot_offset+0x24/0x80\n    .timekeeping_init+0x40/0x29c\n    .start_kernel+0x674/0x8f0\n    start_here_common+0x1c/0x50\n\nUnlike PAPR platforms where RTAS is only used in guests, on the IBM Cell\nmachines Linux runs with MSR[HV] set but also uses RTAS, provided by\nSLOF.\n\nFix it by copying the MSR[HV] bit from the MSR value we\u0027ve just read\nusing mfmsr into the value used for RTAS.\n\nIt seems like we could also fix it using an #ifdef CELL to set MSR[HV],\nbut that doesn\u0027t work because it\u0027s possible to build a single kernel\nimage that runs on both Cell native and pseries."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-23T15:23:21.973Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/8b08d4f97233d8e58fff2fd9d5f86397a49733c5"
        },
        {
          "url": "https://git.kernel.org/stable/c/91926d8b7e71aaf5f84f0cf208fc5a8b7a761050"
        }
      ],
      "title": "powerpc/rtas: Fix RTAS MSR[HV] handling for Cell",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2022-49955",
    "datePublished": "2025-06-18T11:00:17.617Z",
    "dateReserved": "2025-06-18T10:57:27.382Z",
    "dateUpdated": "2026-05-23T15:23:21.973Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2022-49955",
      "date": "2026-09-18",
      "epss": "0.0019",
      "percentile": "0.08943"
    },
    "microsoft_vex": {
      "current_release_date": "2025-11-25T01:35:40.000Z",
      "cve": "CVE-2022-49955",
      "id": "msrc_CVE-2022-49955",
      "initial_release_date": "2025-06-02T00:00:00.000Z",
      "product_status:known_not_affected": "1",
      "source": "Microsoft CSAF VEX",
      "status": "final",
      "title": "powerpc/rtas: Fix RTAS MSR[HV] handling for Cell",
      "url": "https://msrc.microsoft.com/csaf/vex/2025/msrc_cve-2022-49955.json",
      "version": "2"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
                  "arch/powerpc/kernel/rtas_entry.S"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "lessThan": "8b08d4f97233d8e58fff2fd9d5f86397a49733c5",
                    "status": "affected",
                    "version": "b6b1c3ce06ca438eb24e0f45bf0e63ecad0369f5",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "91926d8b7e71aaf5f84f0cf208fc5a8b7a761050",
                    "status": "affected",
                    "version": "b6b1c3ce06ca438eb24e0f45bf0e63ecad0369f5",
                    "versionType": "git"
                  },
                  {
                    "status": "affected",
                    "version": "5ca40fcf0da0ce2b5bc44e7d8b036535955f2e3d",
                    "versionType": "git"
                  },
                  {
                    "status": "affected",
                    "version": "5f4367448f6817c8a0e94dc9736ed84fa8eee4a3",
                    "versionType": "git"
                  },
                  {
                    "status": "affected",
                    "version": "c9c41f0273826a13ac93124e66a4ff45df281ba0",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "5.16",
                    "status": "affected",
                    "version": "5.15.46",
                    "versionType": "semver"
                  },
                  {
                    "lessThan": "5.18",
                    "status": "affected",
                    "version": "5.17.14",
                    "versionType": "semver"
                  },
                  {
                    "lessThan": "5.19",
                    "status": "affected",
                    "version": "5.18.3",
                    "versionType": "semver"
                  }
                ]
              },
              {
                "defaultStatus": "affected",
                "product": "Linux",
                "programFiles": [
                  "arch/powerpc/kernel/rtas_entry.S"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "status": "affected",
                    "version": "5.19"
                  },
                  {
                    "lessThan": "5.19",
                    "status": "unaffected",
                    "version": "0",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.19.*",
                    "status": "unaffected",
                    "version": "5.19.8",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "6.0",
                    "versionType": "original_commit_for_fix"
                  }
                ]
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          }
        ],
        "configurations": [
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "38823576-F70F-46FB-A73D-BFB7068D387D",
                    "versionEndExcluding": "5.16",
                    "versionStartIncluding": "5.15.46",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "53441672-E856-4C9B-92DD-20B8133BE921",
                    "versionEndExcluding": "5.18",
                    "versionStartIncluding": "5.17.14",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "DBEB524B-CE23-4F7F-B400-503BD7FDC334",
                    "versionEndExcluding": "5.19.8",
                    "versionStartIncluding": "5.18.3",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.0:rc1:*:*:*:*:*:*",
                    "matchCriteriaId": "E8BD11A3-8643-49B6-BADE-5029A0117325",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.0:rc2:*:*:*:*:*:*",
                    "matchCriteriaId": "5F0AD220-F6A9-4012-8636-155F1B841FAD",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.0:rc3:*:*:*:*:*:*",
                    "matchCriteriaId": "A46498B3-78E1-4623-AAE1-94D29A42BE4E",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\npowerpc/rtas: Fix RTAS MSR[HV] handling for Cell\n\nThe semi-recent changes to MSR handling when entering RTAS (firmware)\ncause crashes on IBM Cell machines. An example trace:\n\n  kernel tried to execute user page (2fff01a8) - exploit attempt? (uid: 0)\n  BUG: Unable to handle kernel instruction fetch\n  Faulting instruction address: 0x2fff01a8\n  Oops: Kernel access of bad area, sig: 11 [#1]\n  BE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=4 NUMA Cell\n  Modules linked in:\n  CPU: 0 PID: 0 Comm: swapper/0 Tainted: G        W          6.0.0-rc2-00433-gede0a8d3307a #207\n  NIP:  000000002fff01a8 LR: 0000000000032608 CTR: 0000000000000000\n  REGS: c0000000015236b0 TRAP: 0400   Tainted: G        W           (6.0.0-rc2-00433-gede0a8d3307a)\n  MSR:  0000000008001002 \u003cME,RI\u003e  CR: 00000000  XER: 20000000\n  ...\n  NIP 0x2fff01a8\n  LR  0x32608\n  Call Trace:\n    0xc00000000143c5f8 (unreliable)\n    .rtas_call+0x224/0x320\n    .rtas_get_boot_time+0x70/0x150\n    .read_persistent_clock64+0x114/0x140\n    .read_persistent_wall_and_boot_offset+0x24/0x80\n    .timekeeping_init+0x40/0x29c\n    .start_kernel+0x674/0x8f0\n    start_here_common+0x1c/0x50\n\nUnlike PAPR platforms where RTAS is only used in guests, on the IBM Cell\nmachines Linux runs with MSR[HV] set but also uses RTAS, provided by\nSLOF.\n\nFix it by copying the MSR[HV] bit from the MSR value we\u0027ve just read\nusing mfmsr into the value used for RTAS.\n\nIt seems like we could also fix it using an #ifdef CELL to set MSR[HV],\nbut that doesn\u0027t work because it\u0027s possible to build a single kernel\nimage that runs on both Cell native and pseries."
          },
          {
            "lang": "es",
            "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: powerpc/rtas: Correcci\u00f3n del manejo de MSR[HV] de RTAS para Cell. Los cambios recientes en el manejo de MSR al ingresar RTAS (firmware) provocan bloqueos en las m\u00e1quinas IBM Cell. Ejemplo de rastreo: el kernel intent\u00f3 ejecutar la p\u00e1gina de usuario (2fff01a8): \u00bfintento de explotaci\u00f3n? (uid: 0) ERROR: No se puede controlar la obtenci\u00f3n de instrucciones del n\u00facleo Direcci\u00f3n de instrucci\u00f3n err\u00f3nea: 0x2fff01a8 Oops: Acceso del n\u00facleo al \u00e1rea defectuosa, firma: 11 [#1] BE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=4 M\u00f3dulos de celda NUMA vinculados: CPU: 0 PID: 0 Comm: swapper/0 Contaminado: GW 6.0.0-rc2-00433-gede0a8d3307a #207 NIP: 000000002fff01a8 LR: 0000000000032608 CTR: 000000000000000 REGS: c0000000015236b0 TRAP: 0400 Contaminado: GW (6.0.0-rc2-00433-gede0a8d3307a) MSR: 0000000008001002  CR: 00000000 XER: 20000000 ... NIP 0x2fff01a8 LR 0x32608 Rastreo de llamadas: 0xc00000000143c5f8 (no confiable) .rtas_call+0x224/0x320 .rtas_get_boot_time+0x70/0x150 .read_persistent_clock64+0x114/0x140 .read_persistent_wall_and_boot_offset+0x24/0x80 .timekeeping_init+0x40/0x29c A diferencia de las plataformas PAPR, donde RTAS solo se usa en hu\u00e9spedes, en las m\u00e1quinas IBM Cell, Linux se ejecuta con MSR[HV] activado, pero tambi\u00e9n usa RTAS, proporcionado por SLOF. Para solucionarlo, copie el bit MSR[HV] del valor MSR que acabamos de leer con mfmsr al valor usado para RTAS. Parece que tambi\u00e9n podr\u00edamos solucionarlo usando un #ifdef CELL para activar MSR[HV], pero esto no funciona, ya que es posible crear una \u00fanica imagen de kernel que funcione tanto en Cell nativo como en pseries."
          }
        ],
        "id": "CVE-2022-49955",
        "lastModified": "2026-06-17T05:19:37.020",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "LOCAL",
                "availabilityImpact": "HIGH",
                "baseScore": 5.5,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 1.8,
              "impactScore": 3.6,
              "source": "nvd@nist.gov",
              "type": "Primary"
            }
          ]
        },
        "published": "2025-06-18T11:15:22.630",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/8b08d4f97233d8e58fff2fd9d5f86397a49733c5"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/91926d8b7e71aaf5f84f0cf208fc5a8b7a761050"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Analyzed",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-476"
              }
            ],
            "source": "nvd@nist.gov",
            "type": "Primary"
          }
        ]
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Low",
      "current_release_date": "2026-06-30T10:20:05+00:00",
      "cve": "CVE-2022-49955",
      "id": "CVE-2022-49955",
      "initial_release_date": "2022-01-01T00:00:00+00:00",
      "product_status:known_affected": "108",
      "product_status:known_not_affected": "166",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: powerpc/rtas: Fix RTAS MSR[HV] handling for Cell",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2022/cve-2022-49955.json",
      "version": "3"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.


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.