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CVE-2026-23354 (GCVE-0-2026-23354)

Vulnerability from cvelistv5 – Published: 2026-03-25 10:27 – Updated: 2026-05-11 22:05
VLAI
Title
x86/fred: Correct speculative safety in fred_extint()
Summary
In the Linux kernel, the following vulnerability has been resolved: x86/fred: Correct speculative safety in fred_extint() array_index_nospec() is no use if the result gets spilled to the stack, as it makes the believed safe-under-speculation value subject to memory predictions. For all practical purposes, this means array_index_nospec() must be used in the expression that accesses the array. As the code currently stands, it's the wrong side of irqentry_enter(), and 'index' is put into %ebp across the function call. Remove the index variable and reposition array_index_nospec(), so it's calculated immediately before the array access.
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: 14619d912b658ecd9573fb88400d3830a29cadcb , < 3bc5887b0a2b06d2d9c22f1f4f8500490b3ae643 (git)
Affected: 14619d912b658ecd9573fb88400d3830a29cadcb , < e58f1a9b0677de24dcfee0b21393446ec92ff120 (git)
Affected: 14619d912b658ecd9573fb88400d3830a29cadcb , < 92caa5274b99cb6729177232a029ce0dfa6c5f7b (git)
Affected: 14619d912b658ecd9573fb88400d3830a29cadcb , < aa280a08e7d8fae58557acc345b36b3dc329d595 (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.9
Unaffected: 0 , < 6.9 (semver)
Unaffected: 6.12.77 , ≤ 6.12.* (semver)
Unaffected: 6.18.17 , ≤ 6.18.* (semver)
Unaffected: 6.19.7 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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    "redhat_vex": {
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      "cve": "CVE-2026-23354",
      "id": "CVE-2026-23354",
      "initial_release_date": "2026-03-25T00:00:00+00:00",
      "product_status:known_affected": "76",
      "product_status:known_not_affected": "198",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: x86/fred: Correct speculative safety in fred_extint()",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-23354.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-09-11T01:36:58Z",
      "cve": "CVE-2026-23354",
      "id": "CVE-2026-23354",
      "initial_release_date": "2026-03-25T16:55:42Z",
      "product_status:first_fixed": "2",
      "product_status:known_affected": "8",
      "product_status:known_not_affected": "371",
      "product_status:recommended": "256",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-23354",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-23354.json",
      "version": "12"
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  }
}



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  • 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.
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  • 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.


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