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CVE-2026-89481 (GCVE-0-2026-89481)

Vulnerability from cvelistv5 – Published: 2026-09-11 19:43 – Updated: 2026-09-14 12:00
VLAI
Title
nvme-tcp: fix host memory disclosure on R2T for a read command
Summary
In the Linux kernel, the following vulnerability has been resolved: nvme-tcp: fix host memory disclosure on R2T for a read command nvme_tcp_handle_r2t() does not check the direction of the request the R2T refers to. A malicious controller can send an R2T for a READ and the host will answer it: nvme_tcp_setup_h2c_data_pdu() builds the H2CData header and nvme_tcp_try_send_data() sends the request's data buffer. That buffer is the READ destination, so its contents go to the controller. The command then completes normally and nothing is logged. Against a test controller that answers every READ with an R2T, a 4096 byte buffered read returned all 4096 bytes, split over two R2Ts. The pages contained stale kernel data, including an array of struct page pointers. Reject an R2T for a request that is not a write.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 3f2304f8c6d6ed97849057bd16fee99e434ca796 , < 49a4dcf57608ebf6432dbcb203ed25e7ed581445 (git)
Affected: 3f2304f8c6d6ed97849057bd16fee99e434ca796 , < bc4013c7cce58d46f792c8c87bc8c8318a70190e (git)
Affected: 3f2304f8c6d6ed97849057bd16fee99e434ca796 , < a4c3c7310156493797c920b10d8648c07aa05403 (git)
Affected: 3f2304f8c6d6ed97849057bd16fee99e434ca796 , < 3b3d27670c0c890ba7cf1bc3614cab61bde6d25c (git)
Affected: 3f2304f8c6d6ed97849057bd16fee99e434ca796 , < 3a0b05145053a5fad1a2ddb4e4d87b07385e63e5 (git)
Affected: 3f2304f8c6d6ed97849057bd16fee99e434ca796 , < 6efbc52237facda35d2d874fe1765bb4839275d8 (git)
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Linux Linux Affected: 5.0
Unaffected: 0 , < 5.0 (semver)
Unaffected: 6.1.188 , ≤ 6.1.* (semver)
Unaffected: 6.6.157 , ≤ 6.6.* (semver)
Unaffected: 6.12.109 , ≤ 6.12.* (semver)
Unaffected: 6.18.50 , ≤ 6.18.* (semver)
Unaffected: 7.2.4 , ≤ 7.2.* (semver)
Unaffected: 7.3-rc1 , ≤ * (original_commit_for_fix)
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    "datePublished": "2026-09-11T19:43:36.589Z",
    "dateReserved": "2026-09-11T19:38:34.711Z",
    "dateUpdated": "2026-09-14T12:00:18.149Z",
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      "cve": "CVE-2026-89481",
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    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-09-13T06:56:07+00:00",
      "cve": "CVE-2026-89481",
      "id": "CVE-2026-89481",
      "initial_release_date": "2026-09-11T19:43:36.589000+00:00",
      "product_status:known_affected": "2",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: Linux kernel (nvme-tcp): Host memory disclosure",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89481.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "important",
      "current_release_date": "2026-09-16T00:03:07Z",
      "cve": "CVE-2026-89481",
      "id": "CVE-2026-89481",
      "initial_release_date": "2026-09-12T16:27:45Z",
      "product_status:known_affected": "347",
      "product_status:known_not_affected": "6",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-89481",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-89481.json",
      "version": "3"
    }
  }
}



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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.

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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 confirmed: The user expressed doubt about the validity of the vulnerability.
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