CVE-2026-98236

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: net: wwan: mhi_wwan_mbim: check skb_copy_bits() return value mhi_mbim_rx() ignores the return value of skb_copy_bits() when it copies each datagram out of the NTB. The datagram offset and length come from the DPE, which is only checked to lie within the NTB itself, so a modem can point a datagram outside the received skb. The copy then fails and the freshly allocated skbn is passed to netif_rx() with its uninitialized contents still in place, leaking kernel heap memory into the network stack. Free the skb and account an error when the copy fails. Verified in a QEMU guest with a fault injector pointing a DPE outside the received NTB: the copy fails, and the unpatched driver hands the uninitialized skbn to the network stack (observed as "unknown protocol" on bytes that were never written). With this check the failed datagram is dropped and counted as an rx error. Changes in v2: factor the free-and-count sequence out into mhi_mbim_rx_drop(), shared with the unknown-protocol path, as suggested by Loic Poulain.

Severity

Not scored

CVSS score

Not available

Vulnerability status

Received

Source identifier

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Published

2026-10-06 09:18:11.340000

Last modified

2026-10-19 10:18:24.437000

View original CVE JSON

{
  "id": "CVE-2026-98236",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-10-06T09:18:11.340",
  "lastModified": "2026-10-19T10:18:24.437",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: wwan: mhi_wwan_mbim: check skb_copy_bits() return value\n\nmhi_mbim_rx() ignores the return value of skb_copy_bits() when it\ncopies each datagram out of the NTB.  The datagram offset and length\ncome from the DPE, which is only checked to lie within the NTB\nitself, so a modem can point a datagram outside the received skb.\nThe copy then fails and the freshly allocated skbn is passed to\nnetif_rx() with its uninitialized contents still in place, leaking\nkernel heap memory into the network stack.\n\nFree the skb and account an error when the copy fails.\n\n\nVerified in a QEMU guest with a fault injector pointing a DPE\noutside the received NTB: the copy fails, and the unpatched driver\nhands the uninitialized skbn to the network stack (observed as\n\"unknown protocol\" on bytes that were never written).  With this\ncheck the failed datagram is dropped and counted as an rx error.\n\nChanges in v2: factor the free-and-count sequence out into\nmhi_mbim_rx_drop(), shared with the unknown-protocol path, as\nsuggested by Loic Poulain."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/net/wwan/mhi_wwan_mbim.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "aa730a9905b7b079ef2fffdab7f15dbb842f5c7c",
              "lessThan": "650af68435eaee783824457d2ef78cc5c03c1e88",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "aa730a9905b7b079ef2fffdab7f15dbb842f5c7c",
              "lessThan": "350fd3125ee26b5243935fd9e2b4d162ffba430a",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "aa730a9905b7b079ef2fffdab7f15dbb842f5c7c",
              "lessThan": "dd136f1fdd1059f3bc25ede3a8def8f0ee151ce7",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "aa730a9905b7b079ef2fffdab7f15dbb842f5c7c",
              "lessThan": "298659c3677bf622afa9d77549cb4a967f9541e9",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "aa730a9905b7b079ef2fffdab7f15dbb842f5c7c",
              "lessThan": "02eba5f36d20283f144f75d47f0354a85e4f78f0",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "aa730a9905b7b079ef2fffdab7f15dbb842f5c7c",
              "lessThan": "7e98216e9da08b79e07a514d2a4f7646f8c9ccb9",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "aa730a9905b7b079ef2fffdab7f15dbb842f5c7c",
              "lessThan": "31550d585589fde1ae95bf7f7a8188b2d2fdf1c7",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/net/wwan/mhi_wwan_mbim.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "5.15",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "5.15",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.15.222",
              "lessThanOrEqual": "5.15.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.189",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.158",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.112",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.54",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.8",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/02eba5f36d20283f144f75d47f0354a85e4f78f0",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/298659c3677bf622afa9d77549cb4a967f9541e9",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/31550d585589fde1ae95bf7f7a8188b2d2fdf1c7",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/350fd3125ee26b5243935fd9e2b4d162ffba430a",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/650af68435eaee783824457d2ef78cc5c03c1e88",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/7e98216e9da08b79e07a514d2a4f7646f8c9ccb9",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/dd136f1fdd1059f3bc25ede3a8def8f0ee151ce7",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}