CVE-2026-89481

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/3a0b05145053a5fad1a2ddb4e4d87b07385e63e5
https://git.kernel.org/stable/c/3b3d27670c0c890ba7cf1bc3614cab61bde6d25c
https://git.kernel.org/stable/c/49a4dcf57608ebf6432dbcb203ed25e7ed581445
https://git.kernel.org/stable/c/6efbc52237facda35d2d874fe1765bb4839275d8
https://git.kernel.org/stable/c/a4c3c7310156493797c920b10d8648c07aa05403
https://git.kernel.org/stable/c/bc4013c7cce58d46f792c8c87bc8c8318a70190e

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-11 20:19

Updated : 2026-09-14 13:19

NVD link : CVE-2026-89481

Mitre link : CVE-2026-89481

CVE.ORG link : CVE-2026-89481

JSON object : View

Products Affected

No product.

CWE

No CWE.

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