{
  "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-2026-46242",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-46242",
    "idYear": 2026,
    "status": "PUBLISHED",
    "publishedAt": "2026-05-30T12:13:45.594Z",
    "updatedAt": "2026-10-19T19:36:55.705Z",
    "importedAt": "2026-10-24T01:58:14.884Z",
    "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": "eventpoll: fix ep_remove struct eventpoll / struct file UAF",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\neventpoll: fix ep_remove struct eventpoll / struct file UAF\n\nep_remove() (via ep_remove_file()) cleared file->f_ep under\nfile->f_lock but then kept using @file inside the critical section\n(is_file_epoll(), hlist_del_rcu() through the head, spin_unlock).\nA concurrent __fput() taking the eventpoll_release() fastpath in\nthat window observed the transient NULL, skipped\neventpoll_release_file() and ran to f_op->release / file_free().\n\nFor the epoll-watches-epoll case, f_op->release is\nep_eventpoll_release() -> ep_clear_and_put() -> ep_free(), which\nkfree()s the watched struct eventpoll. Its embedded ->refs\nhlist_head is exactly where epi->fllink.pprev points, so the\nsubsequent hlist_del_rcu()'s \"*pprev = next\" scribbles into freed\nkmalloc-192 memory.\n\nIn addition, struct file is SLAB_TYPESAFE_BY_RCU, so the slot\nbacking @file could be recycled by alloc_empty_file() --\nreinitializing f_lock and f_ep -- while ep_remove() is still\nnominally inside that lock. The upshot is an attacker-controllable\nkmem_cache_free() against the wrong slab cache.\n\nPin @file via epi_fget() at the top of ep_remove() and gate the\ncritical section on the pin succeeding. With the pin held @file\ncannot reach refcount zero, which holds __fput() off and\ntransitively keeps the watched struct eventpoll alive across the\nhlist_del_rcu() and the f_lock use, closing both UAFs.\n\nIf the pin fails @file has already reached refcount zero and its\n__fput() is in flight. Because we bailed before clearing f_ep,\nthat path takes the eventpoll_release() slow path into\neventpoll_release_file() and blocks on ep->mtx until the waiter\nside's ep_clear_and_put() drops it. The bailed epi's share of\nep->refcount stays intact, so the trailing ep_refcount_dec_and_test()\nin ep_clear_and_put() cannot free the eventpoll out from under\neventpoll_release_file(); the orphaned epi is then cleaned up\nthere.\n\nA successful pin also proves we are not racing\neventpoll_release_file() on this epi, so drop the now-redundant\nre-check of epi->dying under f_lock. The cheap lockless\nREAD_ONCE(epi->dying) fast-path bailout stays.",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "f2451def095c1743adcfcb0cb5dadc86034e162a",
              "status": "affected",
              "versionType": "git",
              "lessThan": "a10fbbe74e1c743beb1bb312109366667461df8a"
            },
            {
              "version": "a1f93804449d13f97dabd4b996817de4bf1ed67a",
              "status": "affected",
              "versionType": "git",
              "lessThan": "3e1144d2515d28e4312e663ea05eac203101491d"
            },
            {
              "version": "58c9b016e12855286370dfb704c08498edbc857a",
              "status": "affected",
              "versionType": "git",
              "lessThan": "2de4db145b2992da496fea6c51f9839be678ae24"
            },
            {
              "version": "58c9b016e12855286370dfb704c08498edbc857a",
              "status": "affected",
              "versionType": "git",
              "lessThan": "9324de74a3a59b9fde9b62ee45ebaa71458ba2e5"
            },
            {
              "version": "58c9b016e12855286370dfb704c08498edbc857a",
              "status": "affected",
              "versionType": "git",
              "lessThan": "ef4ca02e95363e78977ca04340d44fe3b4b2b81f"
            },
            {
              "version": "58c9b016e12855286370dfb704c08498edbc857a",
              "status": "affected",
              "versionType": "git",
              "lessThan": "ced39b6a8062bac5c18a1c3df85634107eb8664a"
            },
            {
              "version": "58c9b016e12855286370dfb704c08498edbc857a",
              "status": "affected",
              "versionType": "git",
              "lessThan": "a6dc643c69311677c574a0f17a3f4d66a5f3744b"
            },
            {
              "version": "5.15.209",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "5.15.222"
            },
            {
              "version": "6.1.175",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "6.1.178"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "6.4",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "6.4"
            },
            {
              "version": "5.15.222",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "version": "6.1.178",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "version": "6.6.144",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "version": "6.12.95",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "version": "6.18.33",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "version": "7.0.10",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "7.0.*"
            },
            {
              "version": "7.1",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}