CVE-2026-43074 (GCVE-0-2026-43074)

Vulnerability from cvelistv5 – Published: 2026-05-06 07:21 – Updated: 2026-08-05 12:25
VLAI
Title
eventpoll: defer struct eventpoll free to RCU grace period
Summary
In the Linux kernel, the following vulnerability has been resolved: eventpoll: defer struct eventpoll free to RCU grace period In certain situations, ep_free() in eventpoll.c will kfree the epi->ep eventpoll struct while it still being used by another concurrent thread. Defer the kfree() to an RCU callback to prevent UAF.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: f2451def095c1743adcfcb0cb5dadc86034e162a , < 902120be4f44947df6311002addc7faf69bdbff1 (git)
Affected: a1f93804449d13f97dabd4b996817de4bf1ed67a , < a6d57084372161f86660bc4607784420e00efe2c (git)
Affected: 58c9b016e12855286370dfb704c08498edbc857a , < a6566cd33f6f967a7651ebf2ce0dd31572e319cf (git)
Affected: 58c9b016e12855286370dfb704c08498edbc857a , < 5b1173b165421561db29f30afc7e97d940a398a9 (git)
Affected: 58c9b016e12855286370dfb704c08498edbc857a , < 7e8083f5eeedab0f460063b9c2c14c9a4e71a427 (git)
Affected: 58c9b016e12855286370dfb704c08498edbc857a , < ae0bb9c1fb7c2594519aeeb096cf2c3b7837b322 (git)
Affected: 58c9b016e12855286370dfb704c08498edbc857a , < 07712db80857d5d09ae08f3df85a708ecfc3b61f (git)
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Linux Linux Affected: 6.4
Unaffected: 0 , < 6.4 (semver)
Unaffected: 6.6.136 , ≤ 6.6.* (semver)
Unaffected: 6.12.83 , ≤ 6.12.* (semver)
Unaffected: 6.18.24 , ≤ 6.18.* (semver)
Unaffected: 6.19.14 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-07-14T17:32:55+00:00",
      "cve": "CVE-2026-43074",
      "id": "CVE-2026-43074",
      "initial_release_date": "2026-05-06T00:00:00+00:00",
      "product_status:fixed": "1504",
      "product_status:known_affected": "22",
      "product_status:known_not_affected": "76",
      "product_status:under_investigation": "14",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: eventpoll: defer struct eventpoll free to RCU grace period",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-43074.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "important",
      "current_release_date": "2026-07-28T17:17:29Z",
      "cve": "CVE-2026-43074",
      "id": "CVE-2026-43074",
      "initial_release_date": "2026-05-07T02:19:12Z",
      "product_status:first_fixed": "2",
      "product_status:known_affected": "411",
      "product_status:known_not_affected": "181",
      "product_status:recommended": "408",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-43074",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-43074.json",
      "version": "21"
    }
  }
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.