CVE-2026-89481 (GCVE-0-2026-89481)
Vulnerability from cvelistv5
Published
2026-09-11 19:43
Modified
2026-10-19 08:47
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
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.
References
Impacted products
Vendor Product Version
Linux Linux Version: 3f2304f8c6d6ed97849057bd16fee99e434ca796
Version: 3f2304f8c6d6ed97849057bd16fee99e434ca796
Version: 3f2304f8c6d6ed97849057bd16fee99e434ca796
Version: 3f2304f8c6d6ed97849057bd16fee99e434ca796
Version: 3f2304f8c6d6ed97849057bd16fee99e434ca796
Version: 3f2304f8c6d6ed97849057bd16fee99e434ca796
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