FKIE_CVE-2026-68130

Vulnerability from fkie_nvd - Published: 2026-08-10 13:19 - Updated: 2026-08-19 17:20
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved: ksmbd: defer destroy_previous_session() until after NTLM authentication In ntlm_authenticate(), destroy_previous_session() is called using a user pointer resolved from the client-supplied NTLM blob username field before the NTLMv2 response is validated. An authenticated attacker can set the NTLM blob username to match a victim account and set PreviousSessionId to the victim's session ID; destroy_previous_session() destroys the victim's session while ksmbd_decode_ntlmssp_auth_blob() subsequently rejects the request with -EPERM. Move destroy_previous_session() and the prev_id assignment to after ksmbd_decode_ntlmssp_auth_blob() returns success and use sess->user rather than the pre-authentication lookup result. This matches the ordering already used by krb5_authenticate(), where destroy_previous_session() is called only after ksmbd_krb5_authenticate() returns success.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/0ff12308c8a6c16ab68f0a487ffa93d69001dc18
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/18705cace0619fd2123737dcd028147774f38181
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/243f1614ef2aca2d62a744575f1c24b07cd42757
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/370b0ec8822b69c9073265e16b7daaa8201c9a4f
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/5c833074b549e5db125436a6f681af682261f785
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/c74801ee524f477c174a1899782b6c3b6918d407
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/server/smb2pdu.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "370b0ec8822b69c9073265e16b7daaa8201c9a4f",
              "status": "affected",
              "version": "e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9",
              "versionType": "git"
            },
            {
              "lessThan": "5c833074b549e5db125436a6f681af682261f785",
              "status": "affected",
              "version": "e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9",
              "versionType": "git"
            },
            {
              "lessThan": "243f1614ef2aca2d62a744575f1c24b07cd42757",
              "status": "affected",
              "version": "e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9",
              "versionType": "git"
            },
            {
              "lessThan": "18705cace0619fd2123737dcd028147774f38181",
              "status": "affected",
              "version": "e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9",
              "versionType": "git"
            },
            {
              "lessThan": "0ff12308c8a6c16ab68f0a487ffa93d69001dc18",
              "status": "affected",
              "version": "e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9",
              "versionType": "git"
            },
            {
              "lessThan": "c74801ee524f477c174a1899782b6c3b6918d407",
              "status": "affected",
              "version": "e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/server/smb2pdu.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.15"
            },
            {
              "lessThan": "5.15",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.183",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.148",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.101",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.42",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.6",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "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\nksmbd: defer destroy_previous_session() until after NTLM authentication\n\nIn ntlm_authenticate(), destroy_previous_session() is called using a\nuser pointer resolved from the client-supplied NTLM blob username field\nbefore the NTLMv2 response is validated. An authenticated attacker can\nset the NTLM blob username to match a victim account and set\nPreviousSessionId to the victim\u0027s session ID; destroy_previous_session()\ndestroys the victim\u0027s session while ksmbd_decode_ntlmssp_auth_blob()\nsubsequently rejects the request with -EPERM.\n\nMove destroy_previous_session() and the prev_id assignment to after\nksmbd_decode_ntlmssp_auth_blob() returns success and use sess-\u003euser\nrather than the pre-authentication lookup result. This matches the\nordering already used by krb5_authenticate(), where\ndestroy_previous_session() is called only after\nksmbd_krb5_authenticate() returns success."
    }
  ],
  "id": "CVE-2026-68130",
  "lastModified": "2026-08-19T17:20:30.483",
  "metrics": {},
  "published": "2026-08-10T13:19:58.337",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/0ff12308c8a6c16ab68f0a487ffa93d69001dc18"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/18705cace0619fd2123737dcd028147774f38181"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/243f1614ef2aca2d62a744575f1c24b07cd42757"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/370b0ec8822b69c9073265e16b7daaa8201c9a4f"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/5c833074b549e5db125436a6f681af682261f785"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/c74801ee524f477c174a1899782b6c3b6918d407"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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