CVE-2026-81005
Low risk· EPSS 6%Exploitation Probability (EPSS)
Low risk6th percentile - higher than 6% of all known CVEs
Summary
A NULL pointer dereference vulnerability exists in the Linux kernel ipmi_si driver. When IPMI interface registration fails (e.g., BMC does not respond correctly to the Get Device ID command), shutdown_smi() frees si_sm and sets the pointer to NULL, but the in_shutdown flag is not set. The asynchronous redo_bmc_reg work item can then retry communication with the already-cleaned interface, causing start_kcs_transaction() to be called with a NULL pointer and resulting in a kernel crash.
Risk Assessment
A kernel panic causes system unavailability and requires a reboot, potentially leading to service downtime. This vulnerability is particularly relevant in environments with unstable or misbehaving BMC.
Recommendation
Update the Linux kernel to a version containing the fix that sets intf->in_shutdown on the out_err_started path before invoking the shutdown callback. If updating is not possible, consider limiting the use of the ipmi_si driver or ensuring stable BMC communication.
Other vulnerabilities in Linux kernel
See all- CVE-2026-98162Unknown
In the Linux kernel, the smb2_tree_connect() function of the SMB server (ksmbd) leaks a tree connection. When ksmbd_iov_pin_rsp() fails, the newly created tree connection is not disconnected, leading to a resource leak.
- CVE-2026-98160Unknown
In the Linux kernel, the staging rtl8723bs driver's rtw_sdio_if1_init() function frees padapter->HalData with kfree(), even though it was allocated via vzalloc(). Using kfree() to release a vmalloc-backed buffer can lead to memory corruption.
- CVE-2026-100079Unknown
In the Linux kernel, the USB Type-C (ucsi) subsystem's ucsi_register() creates per-instance debugfs entries, but ucsi_unregister() keeps them until ucsi_destroy(). Drivers like ucsi_glink that unregister/register the same UCSI instance across remoteproc restart then try to create an already existing debugfs directory.
- CVE-2026-100078Unknown
In the Linux kernel, the iwlwifi (mei) driver's iwl_mei_write_cyclic_buf() function receives an incorrect first argument — the q_head pointer is passed instead of cldev. The bug has been fixed.
- CVE-2026-100077Unknown
In the Linux kernel, the drm/msm driver does not safely retire a hung submit before GPU recovery completes. Retiring the submit triggers BO free, which can result in GPU pagefaults since the GPU may be actively accessing those BOs.
- CVE-2026-100074Unknown
In the Linux kernel, a bug was fixed where the BPF_REFCOUNT field was not marked as unique, although it should be. The fix addresses this oversight.
- CVE-2026-100073Unknown
In the Linux kernel, a bug in the ext4 filesystem related to transaction overflow during writeback was fixed. A previous fix was too eager in reducing reserved transaction credits, leading to insufficient reservation in some corner cases. The fix uses ext4_meta_trans_blocks() for a correct upper bound estimate.
- CVE-2026-100072Unknown
In the Linux kernel, a problem in the ACPI subsystem was fixed where the use of acpi_get_first_physical_node() in acpi_platform_fill_resource() and acpi_create_platform_device() was unsafe because the returned device could be freed at any time. The fix replaces it with acpi_bus_get_primary_device() and adjusts the code to call it only once.
- CVE-2026-100071Unknown
In the Linux kernel, a memory leak in the HSR (High-availability Seamless Redundancy) module was fixed. When hsr_dev_finalize() fails after registering an RX handler, dynamic nodes learned in that window are not released. The fix frees both dynamic databases in the error unwind path.
- CVE-2026-100070Unknown
In the Linux kernel, a bug in the netfilter nf_nat_sip module was fixed where the offset was not rewound when NAT shrinks the packet. If map_addr() changes the packet length, coff may point to an incorrect position, potentially causing subsequent Contact headers to be skipped and leaking internal network details.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: ipmi: si: Fix NULL pointer dereference after failed registration try_smi_init() allocates new_smi->si_sm and later calls ipmi_register_smi_mod(), which maps to ipmi_add_smi(). During ipmi_add_smi(), the upper IPMI message handler obtains the initial BMC device information through __bmc_get_device_id(). This can fail if the BMC does not return a successful response to the Get Device ID command. When the BMC returns a nonzero completion code, the device-id helper retries the command and eventually returns -EIO if the device ID still cannot be fetched. On this failure path, ipmi_add_smi() logs "Unable to get the device id" and goes to out_err_started, where it invokes the lower driver's shutdown callback. try_smi_init() then logs the returned registration failure: ipmi_si IPI0001:00: IPMI message handler: Unable to get the device id: -5 ipmi_si IPI0001:00: Unable to register device: error -5 For ipmi_si, the shutdown callback is shutdown_smi(), which cleans up the SI state machine data, frees smi_info->si_sm, and sets smi_info->si_sm and smi_info->intf to NULL. However, intf->in_shutdown is not set on this failed-registration rollback path. Therefore, the asynchronous redo_bmc_reg work item can still retry BMC device-id probing after the lower driver has already cleared its SI state machine data. In the observed case, that retry path reached start_next_msg(), which passed the NULL smi_info->si_sm pointer to the selected KCS state machine handler: BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 Workqueue: events redo_bmc_reg [ipmi_msghandler] RIP: start_kcs_transaction+0x2c/0x190 [ipmi_si] Call Trace: start_next_msg+0x50/0x80 [ipmi_si] check_start_timer_thread.part.9+0x3b/0x50 [ipmi_si] sender+0x69/0x80 [ipmi_si] i_ipmi_request+0x2ac/0x9d0 [ipmi_msghandler] __get_device_id.isra.29+0xaa/0x180 [ipmi_msghandler] __bmc_get_device_id+0xef/0x950 [ipmi_msghandler] redo_bmc_reg+0x52/0x60 [ipmi_msghandler] process_one_work+0x1a7/0x360 Set intf->in_shutdown on the out_err_started path before invoking the lower driver's shutdown callback. This prevents later redo_bmc_reg retries from using an interface whose lower driver state has been cleaned up, and applies the same shutdown state to other IPMI interfaces as well.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS