High severity · published May 27, 2026
CVE-2026-46022
misc: ibmasm: fix OOB MMIO read in ibmasm_handle_mouse_interrupt()
7.1
CVSS
0.1%
EPSS
No
On KEV
Description
In the Linux kernel, the following vulnerability has been resolved: misc: ibmasm: fix OOB MMIO read in ibmasm_handle_mouse_interrupt() ibmasm_handle_mouse_interrupt() performs an out-of-bounds MMIO read when the queue reader or writer index from hardware exceeds REMOTE_QUEUE_SIZE (60). A compromised service processor can trigger this by writing an out-of-range value to the reader or writer MMIO register before asserting an interrupt. Since writer is re-read from hardware on every loop iteration, it can also be set to an out-of-range value after the loop has already started. The root cause is that get_queue_reader() and get_queue_writer() return raw readl() values that are passed directly into get_queue_entry(), which computes: queue_begin + reader * sizeof(struct remote_input) with no bounds check. This unchecked MMIO address is then passed to memcpy_fromio(), reading 8 bytes from unintended device registers. For sufficiently large values the address falls outside the PCI BAR mapping entirely, triggering a machine check exception. Fix by checking both indices against REMOTE_QUEUE_SIZE at the top of the loop body, before any call to get_queue_entry(). On an out-of-range value, reset the reader register to 0 via set_queue_reader() before breaking, so that normal queue operation can resume if the corrupted hardware state is transient.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 4% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
2.6.13 before 5.10.258; 5.11 before 5.15.209; 5.16 before 6.1.175; 6.2 before 6.6.140; 6.7 before 6.12.86; 6.13 before 6.18.27; +1 more · source: NVD
LI
Linux · Linux
278d72ae8803ffcd16070c95fe1d53f4466dc741 before 6f6ecc9153df176e956d0664b56f93080b0a45f0; 278d72ae8803ffcd16070c95fe1d53f4466dc741 before bac8643486f854dd53af9b23aea7dbbd9b7c1865; 278d72ae8803ffcd16070c95fe1d53f4466dc741 before f7e5b4eefd7be3e09f8bd5fee63ed478fd7446ab; 278d72ae8803ffcd16070c95fe1d53f4466dc741 before fc7e9a74e32299d7e93e178ca482a0b59ef1595b; 278d72ae8803ffcd16070c95fe1d53f4466dc741 before 07c4f18b303106e6b24492c12b95d48a4b985841; 278d72ae8803ffcd16070c95fe1d53f4466dc741 before 22a16d3eafee92a165c756081587c95850127107; +3 more · source: vendor