CVE-2026-22998: Linux Kernel

High severity, CVSS 7.5. EPSS: 0.8% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: nvme-tcp: fix NULL pointer dereferences in nvmet_tcp_build_pdu_iovec Commit efa56305908b ("nvmet-tcp: Fix a kernel panic when host sends an invalid H2C PDU length") added ttag bounds checking and data_offset validation in nvmet_tcp_handle_h2c_data_pdu(), but it did not validate whether the command's data structures (cmd->req.sg and cmd->iov) have been properly initialized before processing H2C_DATA PDUs. The nvmet_tcp_build_pdu_iovec() function dereferences these pointers without NULL checks. This can be triggered by sending H2C_DATA PDU immediately after the ICREQ/ICRESP handshake, before sending a CONNECT command or NVMe write command. Attack vectors that trigger NULL pointer dereferences: 1. H2C_DATA PDU sent before CONNECT → both pointers NULL 2. H2C_DATA PDU for READ command → cmd->req.sg allocated, cmd->iov NULL 3. H2C_DATA PDU for uninitialized command slot → both pointers NULL The fix validates both cmd->req.sg and cmd->iov before calling nvmet_tcp_build_pdu_iovec(). Both checks are required because: - Uninitialized commands: both NULL - READ commands: cmd->req.sg allocated, cmd->iov NULL - WRITE commands: both allocated

Affected products

• Linux Linux Kernel: from 5.4.268, before 5.5 (fixed in 5.5); from 5.10.209, before 5.10.249 (fixed in 5.10.249); from 5.15.148, before 5.15.199 (fixed in 5.15.199); from 6.1.75, before 6.1.162 (fixed in 6.1.162); from 6.6.14, before 6.6.122 (fixed in 6.6.122); from 6.7.2, before 6.12.67 (fixed in 6.12.67); …

Published 2026-01-25. Last modified 2026-06-17.