{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2024-42240",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2024-42240",
    "idYear": 2024,
    "status": "PUBLISHED",
    "publishedAt": "2024-08-07T15:14:27.977Z",
    "updatedAt": "2026-05-23T15:52:28.123Z",
    "importedAt": "2026-10-24T01:57:16.009Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "x86/bhi: Avoid warning in #DB handler due to BHI mitigation",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nx86/bhi: Avoid warning in #DB handler due to BHI mitigation\n\nWhen BHI mitigation is enabled, if SYSENTER is invoked with the TF flag set\nthen entry_SYSENTER_compat() uses CLEAR_BRANCH_HISTORY and calls the\nclear_bhb_loop() before the TF flag is cleared. This causes the #DB handler\n(exc_debug_kernel()) to issue a warning because single-step is used outside the\nentry_SYSENTER_compat() function.\n\nTo address this issue, entry_SYSENTER_compat() should use CLEAR_BRANCH_HISTORY\nafter making sure the TF flag is cleared.\n\nThe problem can be reproduced with the following sequence:\n\n  $ cat sysenter_step.c\n  int main()\n  { asm(\"pushf; pop %ax; bts $8,%ax; push %ax; popf; sysenter\"); }\n\n  $ gcc -o sysenter_step sysenter_step.c\n\n  $ ./sysenter_step\n  Segmentation fault (core dumped)\n\nThe program is expected to crash, and the #DB handler will issue a warning.\n\nKernel log:\n\n  WARNING: CPU: 27 PID: 7000 at arch/x86/kernel/traps.c:1009 exc_debug_kernel+0xd2/0x160\n  ...\n  RIP: 0010:exc_debug_kernel+0xd2/0x160\n  ...\n  Call Trace:\n  <#DB>\n   ? show_regs+0x68/0x80\n   ? __warn+0x8c/0x140\n   ? exc_debug_kernel+0xd2/0x160\n   ? report_bug+0x175/0x1a0\n   ? handle_bug+0x44/0x90\n   ? exc_invalid_op+0x1c/0x70\n   ? asm_exc_invalid_op+0x1f/0x30\n   ? exc_debug_kernel+0xd2/0x160\n   exc_debug+0x43/0x50\n   asm_exc_debug+0x1e/0x40\n  RIP: 0010:clear_bhb_loop+0x0/0xb0\n  ...\n  </#DB>\n  <TASK>\n   ? entry_SYSENTER_compat_after_hwframe+0x6e/0x8d\n  </TASK>\n\n  [ bp: Massage commit message. ]",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "bd53ec80f21839cfd4d852a6088279d602d67e5b",
              "status": "affected",
              "versionType": "git",
              "lessThan": "db56615e96c439e13783d7715330e824b4fd4b84"
            },
            {
              "version": "07dbb10f153f483e8249acebdffedf922e2ec2e1",
              "status": "affected",
              "versionType": "git",
              "lessThan": "a765679defe1dc1b8fa01928a6ad6361e72a1364"
            },
            {
              "version": "eb36b0dce2138581bc6b5e39d0273cb4c96ded81",
              "status": "affected",
              "versionType": "git",
              "lessThan": "dae3543db8f0cf8ac1a198c3bb4b6e3c24d576cf"
            },
            {
              "version": "7390db8aea0d64e9deb28b8e1ce716f5020c7ee5",
              "status": "affected",
              "versionType": "git",
              "lessThan": "08518d48e5b744620524f0acd7c26c19bda7f513"
            },
            {
              "version": "7390db8aea0d64e9deb28b8e1ce716f5020c7ee5",
              "status": "affected",
              "versionType": "git",
              "lessThan": "ac8b270b61d48fcc61f052097777e3b5e11591e0"
            },
            {
              "version": "8f51637712e4da5be410a1666f8aee0d86eef898",
              "status": "affected",
              "versionType": "git"
            },
            {
              "version": "5.15.154",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "5.15.163"
            },
            {
              "version": "6.1.85",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "6.1.100"
            },
            {
              "version": "6.6.26",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "6.6.41"
            },
            {
              "version": "6.8.5",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "6.9"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "6.9",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "6.9"
            },
            {
              "version": "5.15.163",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "version": "6.1.100",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "version": "6.6.41",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "version": "6.9.10",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.9.*"
            },
            {
              "version": "6.10",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}