CVE-2025-40304 (GCVE-0-2025-40304)

Vulnerability from cvelistv5 – Published: 2025-12-08 00:46 – Updated: 2026-08-05 12:09
VLAI
Title
fbdev: Add bounds checking in bit_putcs to fix vmalloc-out-of-bounds
Summary
In the Linux kernel, the following vulnerability has been resolved: fbdev: Add bounds checking in bit_putcs to fix vmalloc-out-of-bounds Add bounds checking to prevent writes past framebuffer boundaries when rendering text near screen edges. Return early if the Y position is off-screen and clip image height to screen boundary. Break from the rendering loop if the X position is off-screen. When clipping image width to fit the screen, update the character count to match the clipped width to prevent buffer size mismatches. Without the character count update, bit_putcs_aligned and bit_putcs_unaligned receive mismatched parameters where the buffer is allocated for the clipped width but cnt reflects the original larger count, causing out-of-bounds writes.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-16 19:54 UTC
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6843 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 996bfaa7372d6718b6d860bdf78f6618e850c702 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < f0982400648a3e00580253e0c48e991f34d2684c (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 1943b69e87b0ab35032d47de0a7fca9a3d1d6fc1 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < ebc0730b490c7f27340b1222e01dd106e820320d (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 86df8ade88d290725554cefd03101ecd0fbd3752 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 15ba9acafb0517f8359ca30002c189a68ddbb939 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 2d1359e11674ed4274934eac8a71877ae5ae7bbb (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 3637d34b35b287ab830e66048841ace404382b67 (git)
guessed Create a notification for this product.
Linux Linux Affected: 2.6.12
Unaffected: 0 , < 2.6.12 (semver)
Unaffected: 5.4.302 , ≤ 5.4.* (semver)
Unaffected: 5.10.247 , ≤ 5.10.* (semver)
Unaffected: 5.15.197 , ≤ 5.15.* (semver)
Unaffected: 6.1.159 , ≤ 6.1.* (semver)
Unaffected: 6.6.117 , ≤ 6.6.* (semver)
Unaffected: 6.12.58 , ≤ 6.12.* (semver)
Unaffected: 6.17.8 , ≤ 6.17.* (semver)
Unaffected: 6.18 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2025-40304",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-16T19:54:32.739808Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-16T19:54:41.944Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/video/fbdev/core/bitblit.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "996bfaa7372d6718b6d860bdf78f6618e850c702",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "f0982400648a3e00580253e0c48e991f34d2684c",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "1943b69e87b0ab35032d47de0a7fca9a3d1d6fc1",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "ebc0730b490c7f27340b1222e01dd106e820320d",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "86df8ade88d290725554cefd03101ecd0fbd3752",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "15ba9acafb0517f8359ca30002c189a68ddbb939",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "2d1359e11674ed4274934eac8a71877ae5ae7bbb",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "3637d34b35b287ab830e66048841ace404382b67",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/video/fbdev/core/bitblit.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "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": "5.4.302",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.247",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.197",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.159",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.117",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.58",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.17.*",
              "status": "unaffected",
              "version": "6.17.8",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.18",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.4.302",
                  "versionStartIncluding": "2.6.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.247",
                  "versionStartIncluding": "2.6.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.197",
                  "versionStartIncluding": "2.6.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.159",
                  "versionStartIncluding": "2.6.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.117",
                  "versionStartIncluding": "2.6.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.58",
                  "versionStartIncluding": "2.6.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.17.8",
                  "versionStartIncluding": "2.6.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18",
                  "versionStartIncluding": "2.6.12",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfbdev: Add bounds checking in bit_putcs to fix vmalloc-out-of-bounds\n\nAdd bounds checking to prevent writes past framebuffer boundaries when\nrendering text near screen edges. Return early if the Y position is off-screen\nand clip image height to screen boundary. Break from the rendering loop if the\nX position is off-screen. When clipping image width to fit the screen, update\nthe character count to match the clipped width to prevent buffer size\nmismatches.\n\nWithout the character count update, bit_putcs_aligned and bit_putcs_unaligned\nreceive mismatched parameters where the buffer is allocated for the clipped\nwidth but cnt reflects the original larger count, causing out-of-bounds writes."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - Exploitation requires local access to the framebuffer character device (`/dev/fbN` ioctls FBIOPUT_CON2FBMAP / FBIOPUT_VSCREENINFO) and/or a virtual console, plus a write to the console to trigger the redraw. There is no remote or network-reachable path into fbcon\u0027s glyph blitting.\nAC:L - The reproducer is deterministic \u2014 an ioctl puts the VC geometry out of sync with the framebuffer resolution and the very next console redraw performs the out-of-bounds write; syzbot produced a reliable reproducer and confirmed the fix. No race, no memory-layout luck, and no unusual configuration is required (fbcon with DRM fbdev emulation is the default on ordinary systems).\nPR:L - No capability check exists anywhere on the path: `fbcon_set_con2fb_map_ioctl()` and the `FBIOPUT_CON2FBMAP`/`FBIOPUT_VSCREENINFO` handlers perform no `capable()` test, and the VT resize/mode ioctls only require being the owner of the controlling tty. Any unprivileged local user holding the usual graphics/console device access (group `video`, logind uaccess ACLs, Android/kiosk/embedded graphics processes) can reach it.\nUI:N - The attacker performs every step themselves \u2014 issue the ioctl to desynchronize the console geometry, then write bytes to their own console fd to force the redraw. No victim action or interaction is needed.\nS:U - The corruption occurs in kernel virtual memory and is exploited to escalate within the same kernel security authority. No hypervisor, IOMMU, or sandbox boundary is crossed.\nC:H - The bug yields an out-of-bounds write with an attacker-influenced offset into the vmalloc region, adjacent to other DRM GEM shmem vmapped buffers and kernel objects, which is readily leveraged into arbitrary kernel memory disclosure (e.g. by corrupting neighbouring buffer pointers/lengths or other clients\u0027 graphics buffers that the attacker can mmap).\nI:H - This is a controlled out-of-bounds write: the destination offset is derived from attacker-set VC geometry and font metrics, and the written content is attacker-chosen (console text rendered through a user-supplied font via KDFONTOP), giving a powerful kernel write primitive suitable for privilege escalation.\nA:H - The out-of-bounds write past the vmalloc\u0027d framebuffer corrupts adjacent kernel memory or hits an unmapped guard page, producing a KASAN-confirmed vmalloc-out-of-bounds write and, in production kernels, an oops/panic that can be triggered repeatedly."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T12:09:23.704Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/996bfaa7372d6718b6d860bdf78f6618e850c702"
        },
        {
          "url": "https://git.kernel.org/stable/c/f0982400648a3e00580253e0c48e991f34d2684c"
        },
        {
          "url": "https://git.kernel.org/stable/c/1943b69e87b0ab35032d47de0a7fca9a3d1d6fc1"
        },
        {
          "url": "https://git.kernel.org/stable/c/ebc0730b490c7f27340b1222e01dd106e820320d"
        },
        {
          "url": "https://git.kernel.org/stable/c/86df8ade88d290725554cefd03101ecd0fbd3752"
        },
        {
          "url": "https://git.kernel.org/stable/c/15ba9acafb0517f8359ca30002c189a68ddbb939"
        },
        {
          "url": "https://git.kernel.org/stable/c/2d1359e11674ed4274934eac8a71877ae5ae7bbb"
        },
        {
          "url": "https://git.kernel.org/stable/c/3637d34b35b287ab830e66048841ace404382b67"
        }
      ],
      "title": "fbdev: Add bounds checking in bit_putcs to fix vmalloc-out-of-bounds",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-40304",
    "datePublished": "2025-12-08T00:46:29.013Z",
    "dateReserved": "2025-04-16T07:20:57.185Z",
    "dateUpdated": "2026-08-05T12:09:23.704Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2025-40304",
      "date": "2026-10-22",
      "epss": "0.00144",
      "percentile": "0.03365"
    },
    "microsoft_vex": {
      "current_release_date": "2025-12-16T14:39:10.000Z",
      "cve": "CVE-2025-40304",
      "id": "msrc_CVE-2025-40304",
      "initial_release_date": "2025-12-02T00:00:00.000Z",
      "product_status:fixed": "1",
      "product_status:known_affected": "1",
      "source": "Microsoft CSAF VEX",
      "status": "final",
      "title": "fbdev: Add bounds checking in bit_putcs to fix vmalloc-out-of-bounds",
      "url": "https://msrc.microsoft.com/csaf/vex/2025/msrc_cve-2025-40304.json",
      "version": "2"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
                  "drivers/video/fbdev/core/bitblit.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "lessThan": "996bfaa7372d6718b6d860bdf78f6618e850c702",
                    "status": "affected",
                    "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "f0982400648a3e00580253e0c48e991f34d2684c",
                    "status": "affected",
                    "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "1943b69e87b0ab35032d47de0a7fca9a3d1d6fc1",
                    "status": "affected",
                    "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "ebc0730b490c7f27340b1222e01dd106e820320d",
                    "status": "affected",
                    "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "86df8ade88d290725554cefd03101ecd0fbd3752",
                    "status": "affected",
                    "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "15ba9acafb0517f8359ca30002c189a68ddbb939",
                    "status": "affected",
                    "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "2d1359e11674ed4274934eac8a71877ae5ae7bbb",
                    "status": "affected",
                    "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "3637d34b35b287ab830e66048841ace404382b67",
                    "status": "affected",
                    "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
                    "versionType": "git"
                  }
                ]
              },
              {
                "defaultStatus": "affected",
                "product": "Linux",
                "programFiles": [
                  "drivers/video/fbdev/core/bitblit.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "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": "5.4.302",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.10.*",
                    "status": "unaffected",
                    "version": "5.10.247",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.15.*",
                    "status": "unaffected",
                    "version": "5.15.197",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.1.*",
                    "status": "unaffected",
                    "version": "6.1.159",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.6.*",
                    "status": "unaffected",
                    "version": "6.6.117",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.12.*",
                    "status": "unaffected",
                    "version": "6.12.58",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.17.*",
                    "status": "unaffected",
                    "version": "6.17.8",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "6.18",
                    "versionType": "original_commit_for_fix"
                  }
                ]
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfbdev: Add bounds checking in bit_putcs to fix vmalloc-out-of-bounds\n\nAdd bounds checking to prevent writes past framebuffer boundaries when\nrendering text near screen edges. Return early if the Y position is off-screen\nand clip image height to screen boundary. Break from the rendering loop if the\nX position is off-screen. When clipping image width to fit the screen, update\nthe character count to match the clipped width to prevent buffer size\nmismatches.\n\nWithout the character count update, bit_putcs_aligned and bit_putcs_unaligned\nreceive mismatched parameters where the buffer is allocated for the clipped\nwidth but cnt reflects the original larger count, causing out-of-bounds writes."
          },
          {
            "lang": "es",
            "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nfbdev: A\u00f1adir comprobaci\u00f3n de l\u00edmites en bit_putcs para corregir vmalloc-fuera-de-l\u00edmites\n\nA\u00f1adir comprobaci\u00f3n de l\u00edmites para evitar escrituras m\u00e1s all\u00e1 de los l\u00edmites del framebuffer al renderizar texto cerca de los bordes de la pantalla. Retornar anticipadamente si la posici\u00f3n Y est\u00e1 fuera de la pantalla y recortar la altura de la imagen al l\u00edmite de la pantalla. Salir del bucle de renderizado si la posici\u00f3n X est\u00e1 fuera de la pantalla. Al recortar el ancho de la imagen para ajustarse a la pantalla, actualizar el recuento de caracteres para que coincida con el ancho recortado para evitar desajustes de tama\u00f1o de b\u00fafer.\n\nSin la actualizaci\u00f3n del recuento de caracteres, bit_putcs_aligned y bit_putcs_unaligned reciben par\u00e1metros desajustados donde el b\u00fafer se asigna para el ancho recortado pero cnt refleja el recuento original mayor, causando escrituras fuera de l\u00edmites."
          }
        ],
        "id": "CVE-2025-40304",
        "lastModified": "2026-10-14T22:10:00.210",
        "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": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
              "type": "Secondary"
            }
          ],
          "ssvcV203": [
            {
              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "ssvcData": {
                "id": "CVE-2025-40304",
                "options": [
                  {
                    "exploitation": "none"
                  },
                  {
                    "automatable": "no"
                  },
                  {
                    "technicalImpact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-16T19:54:32.739808Z",
                "version": "2.0.3"
              }
            }
          ]
        },
        "published": "2025-12-08T01:16:02.567",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/15ba9acafb0517f8359ca30002c189a68ddbb939"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/1943b69e87b0ab35032d47de0a7fca9a3d1d6fc1"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/2d1359e11674ed4274934eac8a71877ae5ae7bbb"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/3637d34b35b287ab830e66048841ace404382b67"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/86df8ade88d290725554cefd03101ecd0fbd3752"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/996bfaa7372d6718b6d860bdf78f6618e850c702"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/ebc0730b490c7f27340b1222e01dd106e820320d"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/f0982400648a3e00580253e0c48e991f34d2684c"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Deferred"
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-07-30T08:42:59+00:00",
      "cve": "CVE-2025-40304",
      "id": "CVE-2025-40304",
      "initial_release_date": "2025-12-08T00:00:00+00:00",
      "product_status:fixed": "2311",
      "product_status:known_affected": "22",
      "product_status:known_not_affected": "42",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: Linux kernel: Out-of-bounds write in fbdev can lead to privilege escalation, information disclosure, or denial of service.",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-40304.json",
      "version": "3"
    },
    "vulnrichment": {
      "containers": {
        "adp": [
          {
            "metrics": [
              {
                "other": {
                  "content": {
                    "id": "CVE-2025-40304",
                    "options": [
                      {
                        "Exploitation": "none"
                      },
                      {
                        "Automatable": "no"
                      },
                      {
                        "Technical Impact": "partial"
                      }
                    ],
                    "role": "CISA Coordinator",
                    "timestamp": "2026-06-16T19:54:32.739808Z",
                    "version": "2.0.3"
                  },
                  "type": "ssvc"
                }
              }
            ],
            "providerMetadata": {
              "dateUpdated": "2026-06-16T19:54:37.690Z",
              "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "shortName": "CISA-ADP"
            },
            "title": "CISA ADP Vulnrichment"
          }
        ],
        "cna": {
          "affected": [
            {
              "defaultStatus": "unaffected",
              "product": "Linux",
              "programFiles": [
                "drivers/video/fbdev/core/bitblit.c"
              ],
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "vendor": "Linux",
              "versions": [
                {
                  "lessThan": "996bfaa7372d6718b6d860bdf78f6618e850c702",
                  "status": "affected",
                  "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
                  "versionType": "git"
                },
                {
                  "lessThan": "f0982400648a3e00580253e0c48e991f34d2684c",
                  "status": "affected",
                  "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
                  "versionType": "git"
                },
                {
                  "lessThan": "1943b69e87b0ab35032d47de0a7fca9a3d1d6fc1",
                  "status": "affected",
                  "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
                  "versionType": "git"
                },
                {
                  "lessThan": "ebc0730b490c7f27340b1222e01dd106e820320d",
                  "status": "affected",
                  "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
                  "versionType": "git"
                },
                {
                  "lessThan": "86df8ade88d290725554cefd03101ecd0fbd3752",
                  "status": "affected",
                  "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
                  "versionType": "git"
                },
                {
                  "lessThan": "15ba9acafb0517f8359ca30002c189a68ddbb939",
                  "status": "affected",
                  "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
                  "versionType": "git"
                },
                {
                  "lessThan": "2d1359e11674ed4274934eac8a71877ae5ae7bbb",
                  "status": "affected",
                  "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
                  "versionType": "git"
                },
                {
                  "lessThan": "3637d34b35b287ab830e66048841ace404382b67",
                  "status": "affected",
                  "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
                  "versionType": "git"
                }
              ]
            },
            {
              "defaultStatus": "affected",
              "product": "Linux",
              "programFiles": [
                "drivers/video/fbdev/core/bitblit.c"
              ],
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "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": "5.4.302",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "5.10.*",
                  "status": "unaffected",
                  "version": "5.10.247",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "5.15.*",
                  "status": "unaffected",
                  "version": "5.15.197",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "6.1.*",
                  "status": "unaffected",
                  "version": "6.1.159",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "6.6.*",
                  "status": "unaffected",
                  "version": "6.6.117",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "6.12.*",
                  "status": "unaffected",
                  "version": "6.12.58",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "6.17.*",
                  "status": "unaffected",
                  "version": "6.17.8",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "*",
                  "status": "unaffected",
                  "version": "6.18",
                  "versionType": "original_commit_for_fix"
                }
              ]
            }
          ],
          "cpeApplicability": [
            {
              "nodes": [
                {
                  "cpeMatch": [
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "5.4.302",
                      "versionStartIncluding": "2.6.12",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "5.10.247",
                      "versionStartIncluding": "2.6.12",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "5.15.197",
                      "versionStartIncluding": "2.6.12",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "6.1.159",
                      "versionStartIncluding": "2.6.12",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "6.6.117",
                      "versionStartIncluding": "2.6.12",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "6.12.58",
                      "versionStartIncluding": "2.6.12",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "6.17.8",
                      "versionStartIncluding": "2.6.12",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "6.18",
                      "versionStartIncluding": "2.6.12",
                      "vulnerable": true
                    }
                  ],
                  "negate": false,
                  "operator": "OR"
                }
              ]
            }
          ],
          "descriptions": [
            {
              "lang": "en",
              "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfbdev: Add bounds checking in bit_putcs to fix vmalloc-out-of-bounds\n\nAdd bounds checking to prevent writes past framebuffer boundaries when\nrendering text near screen edges. Return early if the Y position is off-screen\nand clip image height to screen boundary. Break from the rendering loop if the\nX position is off-screen. When clipping image width to fit the screen, update\nthe character count to match the clipped width to prevent buffer size\nmismatches.\n\nWithout the character count update, bit_putcs_aligned and bit_putcs_unaligned\nreceive mismatched parameters where the buffer is allocated for the clipped\nwidth but cnt reflects the original larger count, causing out-of-bounds writes."
            }
          ],
          "providerMetadata": {
            "dateUpdated": "2026-05-11T21:46:45.832Z",
            "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "shortName": "Linux"
          },
          "references": [
            {
              "url": "https://git.kernel.org/stable/c/996bfaa7372d6718b6d860bdf78f6618e850c702"
            },
            {
              "url": "https://git.kernel.org/stable/c/f0982400648a3e00580253e0c48e991f34d2684c"
            },
            {
              "url": "https://git.kernel.org/stable/c/1943b69e87b0ab35032d47de0a7fca9a3d1d6fc1"
            },
            {
              "url": "https://git.kernel.org/stable/c/ebc0730b490c7f27340b1222e01dd106e820320d"
            },
            {
              "url": "https://git.kernel.org/stable/c/86df8ade88d290725554cefd03101ecd0fbd3752"
            },
            {
              "url": "https://git.kernel.org/stable/c/15ba9acafb0517f8359ca30002c189a68ddbb939"
            },
            {
              "url": "https://git.kernel.org/stable/c/2d1359e11674ed4274934eac8a71877ae5ae7bbb"
            },
            {
              "url": "https://git.kernel.org/stable/c/3637d34b35b287ab830e66048841ace404382b67"
            }
          ],
          "title": "fbdev: Add bounds checking in bit_putcs to fix vmalloc-out-of-bounds",
          "x_generator": {
            "engine": "bippy-1.2.0"
          }
        }
      },
      "cveMetadata": {
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "assignerShortName": "Linux",
        "cveId": "CVE-2025-40304",
        "datePublished": "2025-12-08T00:46:29.013Z",
        "dateReserved": "2025-04-16T07:20:57.185Z",
        "dateUpdated": "2026-06-16T19:54:41.944Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

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.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

JSON

Loading timeline…




    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.