Vulnerability-Lookup

FKIE_CVE-2025-21704

Vulnerability from fkie_nvd - Published: 2025-02-22 10:15 - Updated: 2026-10-15 02:17

Severity

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

Summary

In the Linux kernel, the following vulnerability has been resolved: usb: cdc-acm: Check control transfer buffer size before access If the first fragment is shorter than struct usb_cdc_notification, we can't calculate an expected_size. Log an error and discard the notification instead of reading lengths from memory outside the received data, which can lead to memory corruption when the expected_size decreases between fragments, causing `expected_size - acm->nb_index` to wrap. This issue has been present since the beginning of git history; however, it only leads to memory corruption since commit ea2583529cd1 ("cdc-acm: reassemble fragmented notifications"). A mitigating factor is that acm_ctrl_irq() can only execute after userspace has opened /dev/ttyACM*; but if ModemManager is running, ModemManager will do that automatically depending on the USB device's vendor/product IDs and its other interfaces.

References

URL	Tags
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/383d516a0ebc8641372b521c8cb717f0f1834831	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/6abb510251e75f875797d8983a830e6731fa281c	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/7828e9363ac4d23b02419bf2a45b9f1d9fb35646	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/871619c2b78fdfe05afb4e8ba548678687beb812	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/90dd2f1b7342b9a671a5ea4160f408037b92b118	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/a4e1ae5c0533964170197e4fb4f33bc8c1db5cd2	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/e563b01208f4d1f609bcab13333b6c0e24ce6a01	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/f64079bef6a8a7823358c3f352ea29a617844636	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://project-zero.issues.chromium.org/issues/395107243	Exploit, Issue Tracking, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108	https://lists.debian.org/debian-lts-announce/2025/03/msg00028.html
af854a3a-2127-422b-91ae-364da2661108	https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html
0b142b55-0307-4c5a-b3c9-f314f3fb7c5e	https://cert-portal.siemens.com/productcert/html/ssa-265688.html
0b142b55-0307-4c5a-b3c9-f314f3fb7c5e	https://cert-portal.siemens.com/productcert/html/ssa-784472.html

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	2.6.12
linux	linux_kernel	2.6.12
linux	linux_kernel	2.6.12
linux	linux_kernel	2.6.12
linux	linux_kernel	2.6.12
linux	linux_kernel	6.14
linux	linux_kernel	6.14

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/usb/class/cdc-acm.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
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            {
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              "versionType": "git"
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              "versionType": "git"
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              "lessThan": "f64079bef6a8a7823358c3f352ea29a617844636",
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          ],
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          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "2.6.12"
            },
            {
              "lessThan": "2.6.12",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.4.*",
              "status": "unaffected",
              "version": "5.4.291",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.235",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.179",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.129",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.79",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.16",
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            },
            {
              "lessThanOrEqual": "6.13.*",
              "status": "unaffected",
              "version": "6.13.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.14",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "affectedData": [
        {
          "defaultStatus": "unknown",
          "product": "SIMATIC S7-1500 TM MFP - GNU/Linux subsystem",
          "vendor": "Siemens",
          "versions": [
            {
              "lessThan": "*",
              "status": "affected",
              "version": "0",
              "versionType": "custom"
            }
          ]
        },
        {
          "defaultStatus": "unknown",
          "product": "SIMATIC S7-1500 TM MFP - GNU/Linux subsystem",
          "vendor": "Siemens",
          "versions": [
            {
              "lessThan": "*",
              "status": "affected",
              "version": "0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "552A6C63-5778-4C1E-933C-E06FC7223B21",
              "versionEndExcluding": "5.4.291",
              "versionStartIncluding": "2.6.13",
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              "matchCriteriaId": "2DA5009C-C9B9-4A1D-9B96-78427E8F232C",
              "versionEndExcluding": "6.1.129",
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              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "B16AADE5-B2FD-4C14-B4E4-85E8EDAFE775",
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              "versionStartIncluding": "6.2",
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            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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            {
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              "versionEndExcluding": "6.13.4",
              "versionStartIncluding": "6.13",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:2.6.12:-:*:*:*:*:*:*",
              "matchCriteriaId": "6F62EECE-8FB1-4D57-85D8-CB9E23CF313C",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:2.6.12:rc2:*:*:*:*:*:*",
              "matchCriteriaId": "4F76C298-81DC-43E4-8FC9-DC005A2116EF",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:2.6.12:rc3:*:*:*:*:*:*",
              "matchCriteriaId": "0AB349B2-3F78-4197-882B-90ADB3BF645A",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:2.6.12:rc4:*:*:*:*:*:*",
              "matchCriteriaId": "6AC88830-A9BC-4607-B572-A4B502FC9FD0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:2.6.12:rc5:*:*:*:*:*:*",
              "matchCriteriaId": "476CB3A5-D022-4F13-AAEF-CB6A5785516A",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:*",
              "matchCriteriaId": "186716B6-2B66-4BD0-852E-D48E71C0C85F",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:*",
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              "vulnerable": true
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          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nusb: cdc-acm: Check control transfer buffer size before access\n\nIf the first fragment is shorter than struct usb_cdc_notification, we can\u0027t\ncalculate an expected_size. Log an error and discard the notification\ninstead of reading lengths from memory outside the received data, which can\nlead to memory corruption when the expected_size decreases between\nfragments, causing `expected_size - acm-\u003enb_index` to wrap.\n\nThis issue has been present since the beginning of git history; however,\nit only leads to memory corruption since commit ea2583529cd1\n(\"cdc-acm: reassemble fragmented notifications\").\n\nA mitigating factor is that acm_ctrl_irq() can only execute after userspace\nhas opened /dev/ttyACM*; but if ModemManager is running, ModemManager will\ndo that automatically depending on the USB device\u0027s vendor/product IDs and\nits other interfaces."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: usb: cdc-acm: Verificar el tama\u00f1o del b\u00fafer de transferencia de control antes del acceso Si el primer fragmento es m\u00e1s corto que struct usb_cdc_notification, no podemos calcular un expected_size. Registra un error y descarta la notificaci\u00f3n en lugar de leer longitudes de la memoria fuera de los datos recibidos, lo que puede provocar una corrupci\u00f3n de la memoria cuando el expected_size disminuye entre fragmentos, lo que hace que `expected_size - acm-\u0026gt;nb_index` se ajuste. Este problema ha estado presente desde el comienzo de la historia de git; sin embargo, solo conduce a la corrupci\u00f3n de la memoria desde el commit ea2583529cd1 (\"cdc-acm: reensamblar notificaciones fragmentadas\"). Un factor atenuante es que acm_ctrl_irq() solo se puede ejecutar despu\u00e9s de que el espacio de usuario haya abierto /dev/ttyACM*; pero si ModemManager se est\u00e1 ejecutando, ModemManager lo har\u00e1 autom\u00e1ticamente dependiendo de los ID de proveedor/producto del dispositivo USB y sus otras interfaces."
    }
  ],
  "id": "CVE-2025-21704",
  "lastModified": "2026-10-15T02:17:28.313",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2025-02-22T10:15:11.263",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/383d516a0ebc8641372b521c8cb717f0f1834831"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/6abb510251e75f875797d8983a830e6731fa281c"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/7828e9363ac4d23b02419bf2a45b9f1d9fb35646"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/871619c2b78fdfe05afb4e8ba548678687beb812"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/90dd2f1b7342b9a671a5ea4160f408037b92b118"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/a4e1ae5c0533964170197e4fb4f33bc8c1db5cd2"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/e563b01208f4d1f609bcab13333b6c0e24ce6a01"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/f64079bef6a8a7823358c3f352ea29a617844636"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Exploit",
        "Issue Tracking",
        "Third Party Advisory"
      ],
      "url": "https://project-zero.issues.chromium.org/issues/395107243"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "https://lists.debian.org/debian-lts-announce/2025/03/msg00028.html"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html"
    },
    {
      "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
      "url": "https://cert-portal.siemens.com/productcert/html/ssa-265688.html"
    },
    {
      "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
      "url": "https://cert-portal.siemens.com/productcert/html/ssa-784472.html"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-787"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}

CVE-2025-21704 (GCVE-0-2025-21704)

Vulnerability from cvelistv5 – Published: 2025-02-22 09:43 – Updated: 2026-10-15 01:03

Title

usb: cdc-acm: Check control transfer buffer size before access

Summary

Severity

No CVSS data available.

Assigner

Linux CNA under the mitre root

CNA scorecard D 53/100 over 7018 records in the last 180 days details

References

13 references

URL	Tags
https://git.kernel.org/stable/c/a4e1ae5c053396417…
https://git.kernel.org/stable/c/90dd2f1b7342b9a67…
https://git.kernel.org/stable/c/871619c2b78fdfe05…
https://git.kernel.org/stable/c/7828e9363ac4d23b0…
https://git.kernel.org/stable/c/6abb510251e75f875…
https://git.kernel.org/stable/c/f64079bef6a8a7823…
https://git.kernel.org/stable/c/383d516a0ebc86413…
https://git.kernel.org/stable/c/e563b01208f4d1f60…
https://project-zero.issues.chromium.org/issues/3…
https://lists.debian.org/debian-lts-announce/2025…
https://lists.debian.org/debian-lts-announce/2025…
https://cert-portal.siemens.com/productcert/html/…
https://cert-portal.siemens.com/productcert/html/…

Impacted products

3 products

Vendor	Product	Version
Linux	Linux	Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < a4e1ae5c0533964170197e4fb4f33bc8c1db5cd2 (git) Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 90dd2f1b7342b9a671a5ea4160f408037b92b118 (git) Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 871619c2b78fdfe05afb4e8ba548678687beb812 (git) Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 7828e9363ac4d23b02419bf2a45b9f1d9fb35646 (git) Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 6abb510251e75f875797d8983a830e6731fa281c (git) Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < f64079bef6a8a7823358c3f352ea29a617844636 (git) Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 383d516a0ebc8641372b521c8cb717f0f1834831 (git) Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < e563b01208f4d1f609bcab13333b6c0e24ce6a01 (git)
Linux	Linux	Affected: 2.6.12 Unaffected: 0 , < 2.6.12 (semver) Unaffected: 5.4.291 , ≤ 5.4.* (semver) Unaffected: 5.10.235 , ≤ 5.10.* (semver) Unaffected: 5.15.179 , ≤ 5.15.* (semver) Unaffected: 6.1.129 , ≤ 6.1.* (semver) Unaffected: 6.6.79 , ≤ 6.6.* (semver) Unaffected: 6.12.16 , ≤ 6.12.* (semver) Unaffected: 6.13.4 , ≤ 6.13.* (semver) Unaffected: 6.14 , ≤ * (original_commit_for_fix)
Siemens	SIMATIC S7-1500 TM MFP - GNU/Linux subsystem	Affected: 0 , < * (custom)

Show details on NVD website

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          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
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            "url": "https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html"
          },
          {
            "url": "https://lists.debian.org/debian-lts-announce/2025/03/msg00028.html"
          }
        ],
        "title": "CVE Program Container"
      },
      {
        "affected": [
          {
            "defaultStatus": "unknown",
            "product": "SIMATIC S7-1500 TM MFP - GNU/Linux subsystem",
            "vendor": "Siemens",
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              {
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          "orgId": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
          "shortName": "siemens-SADP"
        },
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          {
            "url": "https://cert-portal.siemens.com/productcert/html/ssa-265688.html"
          },
          {
            "url": "https://cert-portal.siemens.com/productcert/html/ssa-784472.html"
          }
        ],
        "x_adpType": "supplier"
      }
    ],
    "cna": {
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          "product": "Linux",
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            "drivers/usb/class/cdc-acm.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
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              "versionType": "git"
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            "drivers/usb/class/cdc-acm.c"
          ],
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          "vendor": "Linux",
          "versions": [
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              "status": "affected",
              "version": "2.6.12"
            },
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              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
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              "status": "unaffected",
              "version": "5.4.291",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.235",
              "versionType": "semver"
            },
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              "status": "unaffected",
              "version": "5.15.179",
              "versionType": "semver"
            },
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              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.129",
              "versionType": "semver"
            },
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              "lessThanOrEqual": "6.6.*",
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              "version": "6.6.79",
              "versionType": "semver"
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              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.16",
              "versionType": "semver"
            },
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              "lessThanOrEqual": "6.13.*",
              "status": "unaffected",
              "version": "6.13.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.14",
              "versionType": "original_commit_for_fix"
            }
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        }
      ],
      "cpeApplicability": [
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nusb: cdc-acm: Check control transfer buffer size before access\n\nIf the first fragment is shorter than struct usb_cdc_notification, we can\u0027t\ncalculate an expected_size. Log an error and discard the notification\ninstead of reading lengths from memory outside the received data, which can\nlead to memory corruption when the expected_size decreases between\nfragments, causing `expected_size - acm-\u003enb_index` to wrap.\n\nThis issue has been present since the beginning of git history; however,\nit only leads to memory corruption since commit ea2583529cd1\n(\"cdc-acm: reassemble fragmented notifications\").\n\nA mitigating factor is that acm_ctrl_irq() can only execute after userspace\nhas opened /dev/ttyACM*; but if ModemManager is running, ModemManager will\ndo that automatically depending on the USB device\u0027s vendor/product IDs and\nits other interfaces."
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        },
        {
          "url": "https://project-zero.issues.chromium.org/issues/395107243"
        }
      ],
      "title": "usb: cdc-acm: Check control transfer buffer size before access",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
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  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-21704",
    "datePublished": "2025-02-22T09:43:37.377Z",
    "dateReserved": "2024-12-29T08:45:45.751Z",
    "dateUpdated": "2026-10-15T01:03:26.561Z",
    "state": "PUBLISHED"
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}

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.

Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

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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.

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