CVE-2026-98728

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: tpm: fix off-by-four bounds check in tpm2_get_random() When the response carries the TPM2_ST_SESSIONS tag, tpm2_get_random() skips the 4-byte parameter size field before locating the random data, but the bounds check still validates the response length against TPM_HEADER_SIZE. A truncated response can pass the check and make memcpy() read up to 4 bytes past the response end, so stale buffer contents end up in the caller's random bytes. Fix this by checking the response length against 'offset', which already includes the skipped parameter size field.

Severity

Not scored

CVSS score

Not available

Vulnerability status

Received

Source identifier

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

Published

2026-10-18 16:17:26.430000

Last modified

2026-10-19 10:19:36.963000

View original CVE JSON

{
  "id": "CVE-2026-98728",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-10-18T16:17:26.430",
  "lastModified": "2026-10-19T10:19:36.963",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntpm: fix off-by-four bounds check in tpm2_get_random()\n\nWhen the response carries the TPM2_ST_SESSIONS tag, tpm2_get_random()\nskips the 4-byte parameter size field before locating the random data,\nbut the bounds check still validates the response length against\nTPM_HEADER_SIZE.  A truncated response can pass the check and make\nmemcpy() read up to 4 bytes past the response end, so stale buffer\ncontents end up in the caller's random bytes.\n\nFix this by checking the response length against 'offset', which\nalready includes the skipped parameter size field."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/char/tpm/tpm2-cmd.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "1b6d7f9eb150305dcb0da4f7101a8d30dcdf0497",
              "lessThan": "be54101992c2c5218be0e0a87827ccc96e3089af",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "1b6d7f9eb150305dcb0da4f7101a8d30dcdf0497",
              "lessThan": "e30a2406408d2df6d9cd48c2e59e913cf266a05a",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "1b6d7f9eb150305dcb0da4f7101a8d30dcdf0497",
              "lessThan": "42bb6216b861e892512128219ff23010d656ba14",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "1b6d7f9eb150305dcb0da4f7101a8d30dcdf0497",
              "lessThan": "9b522400bf5c082feb9a0037a053ea822a2c7e4d",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/char/tpm/tpm2-cmd.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.10",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.10",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.113",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.56",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.10",
              "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/42bb6216b861e892512128219ff23010d656ba14",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/9b522400bf5c082feb9a0037a053ea822a2c7e4d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/be54101992c2c5218be0e0a87827ccc96e3089af",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/e30a2406408d2df6d9cd48c2e59e913cf266a05a",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}