« Volver al listado

CVE-2024-50072

Estado: ModificadaMedia (5.5)—

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

x86/bugs: Use code segment selector for VERW operand

Robert Gill reported below #GP in 32-bit mode when dosemu software was executing vm86() system call:

This only happens in 32-bit mode when VERW based mitigations like MDS/RFDS are enabled. This is because segment registers with an arbitrary user value can result in #GP when executing VERW. Intel SDM vol. 2C documents the following behavior for VERW instruction:

CLEAR_CPU_BUFFERS macro executes VERW instruction before returning to user space. Use %cs selector to reference VERW operand. This ensures VERW will not #GP for an arbitrary user %ds.

Leer descripción completaMostrar menos

[ mingo: Fixed the SOB chain. ]

Detalles técnicos trazas, registros y código del informe original
  general protection fault: 0000 [#1] PREEMPT SMP
  CPU: 4 PID: 4610 Comm: dosemu.bin Not tainted 6.6.21-gentoo-x86 #1
  Hardware name: Dell Inc. PowerEdge 1950/0H723K, BIOS 2.7.0 10/30/2010
  EIP: restore_all_switch_stack+0xbe/0xcf
  EAX: 00000000 EBX: 00000000 ECX: 00000000 EDX: 00000000
  ESI: 00000000 EDI: 00000000 EBP: 00000000 ESP: ff8affdc
  DS: 0000 ES: 0000 FS: 0000 GS: 0033 SS: 0068 EFLAGS: 00010046
  CR0: 80050033 CR2: 00c2101c CR3: 04b6d000 CR4: 000406d0
  Call Trace:
   show_regs+0x70/0x78
   die_addr+0x29/0x70
   exc_general_protection+0x13c/0x348
   exc_bounds+0x98/0x98
   handle_exception+0x14d/0x14d
   exc_bounds+0x98/0x98
   restore_all_switch_stack+0xbe/0xcf
   exc_bounds+0x98/0x98
   restore_all_switch_stack+0xbe/0xcf

  #GP(0) - If a memory operand effective address is outside the CS, DS, ES,
	   FS, or GS segment limit.

CVSS

Probabilidad de explotación (EPSS)

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

Tecnologías afectadas (1)

CWE

Referencias

JSON original (NVD)

Mostrar
{
  "id": "CVE-2024-50072",
  "cveTags": [],
  "metrics": {
    "cvssMetricV31": [
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 5.5,
          "attackVector": "LOCAL",
          "baseSeverity": "MEDIUM",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "NONE"
        },
        "impactScore": 3.6,
        "exploitabilityScore": 1.8
      }
    ]
  },
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "50f021f0b985629accf10481a6e89af8b9700583",
              "lessThan": "bfd1d223d80cb29a210caa1bd5e21f0816d58f02",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "d54de9f2a127090f2017184e8257795b487d5312",
              "lessThan": "ada431c6c31a2c8c37991c46089af5caa23a9c6e",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "2e3087505ddb8ba2d3d4c81306cca11e868fcdb9",
              "lessThan": "38c5fe74f3bef98f75d16effa49836d50c9b6097",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "ca13d8cd8dac25558da4ee8df4dc70e8e7f9d762",
              "lessThan": "481b477ab63c7245715a3e57ba79eb87c2dc0d02",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "a0e2dab44d22b913b4c228c8b52b2a104434b0b3",
              "lessThan": "bc576fbaf82deded606e69a00efe9752136bf91d",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "a0e2dab44d22b913b4c228c8b52b2a104434b0b3",
              "lessThan": "e4d2102018542e3ae5e297bc6e229303abff8a0f",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "51eca9f1fd047b500137d021f882d93f03280118",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "5.10.215",
              "lessThan": "5.10.229",
              "versionType": "semver"
            },
            {
              "status": "affected",
              "version": "5.15.154",
              "lessThan": "5.15.171",
              "versionType": "semver"
            },
            {
              "status": "affected",
              "version": "6.1.81",
              "lessThan": "6.1.116",
              "versionType": "semver"
            },
            {
              "status": "affected",
              "version": "6.6.21",
              "lessThan": "6.6.58",
              "versionType": "semver"
            },
            {
              "status": "affected",
              "version": "6.7.9",
              "lessThan": "6.8",
              "versionType": "semver"
            }
          ],
          "programFiles": [
            "arch/x86/include/asm/nospec-branch.h"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.8"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "6.8",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "5.10.229",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "status": "unaffected",
              "version": "5.15.171",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "status": "unaffected",
              "version": "6.1.116",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "status": "unaffected",
              "version": "6.6.58",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "status": "unaffected",
              "version": "6.11.5",
              "versionType": "semver",
              "lessThanOrEqual": "6.11.*"
            },
            {
              "status": "unaffected",
              "version": "6.12",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "arch/x86/include/asm/nospec-branch.h"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2024-10-29T01:15:04.393",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/38c5fe74f3bef98f75d16effa49836d50c9b6097",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/481b477ab63c7245715a3e57ba79eb87c2dc0d02",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ada431c6c31a2c8c37991c46089af5caa23a9c6e",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/bc576fbaf82deded606e69a00efe9752136bf91d",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/bfd1d223d80cb29a210caa1bd5e21f0816d58f02",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/e4d2102018542e3ae5e297bc6e229303abff8a0f",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    }
  ],
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "NVD-CWE-noinfo"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nx86/bugs: Use code segment selector for VERW operand\n\nRobert Gill reported below #GP in 32-bit mode when dosemu software was\nexecuting vm86() system call:\n\n  general protection fault: 0000 [#1] PREEMPT SMP\n  CPU: 4 PID: 4610 Comm: dosemu.bin Not tainted 6.6.21-gentoo-x86 #1\n  Hardware name: Dell Inc. PowerEdge 1950/0H723K, BIOS 2.7.0 10/30/2010\n  EIP: restore_all_switch_stack+0xbe/0xcf\n  EAX: 00000000 EBX: 00000000 ECX: 00000000 EDX: 00000000\n  ESI: 00000000 EDI: 00000000 EBP: 00000000 ESP: ff8affdc\n  DS: 0000 ES: 0000 FS: 0000 GS: 0033 SS: 0068 EFLAGS: 00010046\n  CR0: 80050033 CR2: 00c2101c CR3: 04b6d000 CR4: 000406d0\n  Call Trace:\n   show_regs+0x70/0x78\n   die_addr+0x29/0x70\n   exc_general_protection+0x13c/0x348\n   exc_bounds+0x98/0x98\n   handle_exception+0x14d/0x14d\n   exc_bounds+0x98/0x98\n   restore_all_switch_stack+0xbe/0xcf\n   exc_bounds+0x98/0x98\n   restore_all_switch_stack+0xbe/0xcf\n\nThis only happens in 32-bit mode when VERW based mitigations like MDS/RFDS\nare enabled. This is because segment registers with an arbitrary user value\ncan result in #GP when executing VERW. Intel SDM vol. 2C documents the\nfollowing behavior for VERW instruction:\n\n  #GP(0) - If a memory operand effective address is outside the CS, DS, ES,\n\t   FS, or GS segment limit.\n\nCLEAR_CPU_BUFFERS macro executes VERW instruction before returning to user\nspace. Use %cs selector to reference VERW operand. This ensures VERW will\nnot #GP for an arbitrary user %ds.\n\n[ mingo: Fixed the SOB chain. ]"
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: x86/bugs: Usar selector de segmento de código para el operando VERW Robert Gill informó lo siguiente: #GP en modo de 32 bits cuando el software dosemu estaba ejecutando la llamada al sistema vm86(): error de protección general: 0000 [#1] PREEMPT SMP CPU: 4 PID: 4610 Comm: dosemu.bin No contaminado 6.6.21-gentoo-x86 #1 Nombre del hardware: Dell Inc. PowerEdge 1950/0H723K, BIOS 2.7.0 30/10/2010 EIP: restore_all_switch_stack+0xbe/0xcf EAX: 00000000 EBX: 00000000 ECX: 00000000 EDX: 00000000 ESI: 00000000 EDI: 00000000 EBP: 00000000 ESP: ff8affdc DS: 0000 ES: 0000 FS: 0000 GS: 0033 SS: 0068 EFLAGS: 00010046 CR0: 80050033 CR2: 00c2101c CR3: 04b6d000 CR4: 000406d0 Seguimiento de llamadas: show_regs+0x70/0x78 die_addr+0x29/0x70 exc_general_protection+0x13c/0x348 exc_bounds+0x98/0x98 handle_exception+0x14d/0x14d exc_bounds+0x98/0x98 restore_all_switch_stack+0xbe/0xcf exc_bounds+0x98/0x98 restore_all_switch_stack+0xbe/0xcf Esto solo sucede en el modo de 32 bits cuando se habilitan las mitigaciones basadas en VERW como MDS/RFDS. Esto se debe a que los registros de segmento con un valor de usuario arbitrario pueden generar #GP al ejecutar VERW. Intel SDM vol. 2C documenta el siguiente comportamiento para la instrucción VERW: #GP(0) - Si la dirección efectiva de un operando de memoria está fuera del límite de segmento CS, DS, ES, FS o GS. La macro CLEAR_CPU_BUFFERS ejecuta la instrucción VERW antes de regresar al espacio de usuario. Use el selector %cs para hacer referencia al operando VERW. Esto garantiza que VERW no genere #GP para un usuario arbitrario %ds. [ mingo: Se corrigió la cadena SOB. ]"
    }
  ],
  "lastModified": "2026-06-17T08:03:30.740",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "5E2C9DA6-EADC-4426-9A6E-CF06497716BE",
              "versionEndExcluding": "5.11",
              "versionStartIncluding": "5.10.215"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "21EE109E-592F-4A01-B5D2-F078967481BA",
              "versionEndExcluding": "5.16",
              "versionStartIncluding": "5.15.154"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "67A7652D-50D6-4825-AB66-ECE5A0A5DC3A",
              "versionEndExcluding": "6.2",
              "versionStartIncluding": "6.1.81"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "A9536C02-22D6-445E-A8AF-FF25762F8DF4",
              "versionEndExcluding": "6.6.58",
              "versionStartIncluding": "6.6.21"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "6E62D61A-F704-44DB-A311-17B7534DA7BC",
              "versionEndExcluding": "6.11.5",
              "versionStartIncluding": "6.7"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "739125EE-99C1-42E1-B870-04FD5010BA66",
              "versionEndExcluding": "6.8",
              "versionStartIncluding": "6.7.9"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.12:rc1:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "7F361E1D-580F-4A2D-A509-7615F73167A1"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.12:rc2:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "925478D0-3E3D-4E6F-ACD5-09F28D5DF82C"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.12:rc3:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "3C95E234-D335-4B6C-96BF-E2CEBD8654ED"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}