CVE-2026-22998

Summary

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 Software

VendorProductVersion RangeStatus
LinuxLinuxf775f2621c2ac5cc3a0b3a64665dad4fb146e510 < baabe43a0edefac8cd7b981ff87f967f6034dafeaffected
LinuxLinux4cb3cf7177ae3666be7fb27d4ad4d72a295fb02d < 76abc83a9d25593c2b7613c549413079c14a4686affected
LinuxLinux2871aa407007f6f531fae181ad252486e022df42 < 7d75570002929d20e40110d6b03e46202c9d1bc7affected
LinuxLinux24e05760186dc070d3db190ca61efdbce23afc88 < fdecd3b6aac10d5a18d0dc500fe57f8648b66cd4affected
LinuxLinuxefa56305908ba20de2104f1b8508c6a7401833be < 3def5243150716be86599c2a1767c29c68838b6daffected
LinuxLinuxefa56305908ba20de2104f1b8508c6a7401833be < 374b095e265fa27465f34780e0eb162ff1bef913affected
LinuxLinuxefa56305908ba20de2104f1b8508c6a7401833be < 32b63acd78f577b332d976aa06b56e70d054cbbaaffected
LinuxLinuxee5e7632e981673f42a50ade25e71e612e543d9daffected
LinuxLinux70154e8d015c9b4fb56c1a2ef1fc8b83d45c7f68affected
LinuxLinux5.10.209 < 5.10.249affected
LinuxLinux5.15.148 < 5.15.199affected
LinuxLinux6.1.75 < 6.1.162affected
LinuxLinux6.6.14 < 6.6.122affected
LinuxLinux5.4.268 < 5.5affected
LinuxLinux6.7.2 < 6.8affected
LinuxLinux6.8affected
LinuxLinux0 < 6.8unaffected
LinuxLinux5.10.249 <= 5.10.*unaffected
LinuxLinux5.15.199 <= 5.15.*unaffected
LinuxLinux6.1.162 <= 6.1.*unaffected
LinuxLinux6.6.122 <= 6.6.*unaffected
LinuxLinux6.12.67 <= 6.12.*unaffected
LinuxLinux6.18.7 <= 6.18.*unaffected
LinuxLinux6.19 <= *unaffected

Weaknesses

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: yes
    • Technical Impact: partial

References