High severity · published Sep 11, 2026
CVE-2026-89481
nvme-tcp: fix host memory disclosure on R2T for a read command
7.5
CVSS
0.4%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 35% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
Linux · Linux
3f2304f8c6d6ed97849057bd16fee99e434ca796 before 49a4dcf57608ebf6432dbcb203ed25e7ed581445; 3f2304f8c6d6ed97849057bd16fee99e434ca796 before bc4013c7cce58d46f792c8c87bc8c8318a70190e; 3f2304f8c6d6ed97849057bd16fee99e434ca796 before a4c3c7310156493797c920b10d8648c07aa05403; 3f2304f8c6d6ed97849057bd16fee99e434ca796 before 3b3d27670c0c890ba7cf1bc3614cab61bde6d25c; 3f2304f8c6d6ed97849057bd16fee99e434ca796 before 3a0b05145053a5fad1a2ddb4e4d87b07385e63e5; 3f2304f8c6d6ed97849057bd16fee99e434ca796 before 6efbc52237facda35d2d874fe1765bb4839275d8; +1 more · source: vendor