IM
IronMonkey Threat Research

CVE-2026-46064 HIGH

Published: 2026-05-27 | Last Modified: 2026-06-24 | Status: Undergoing Analysis

Description

In the Linux kernel, the following vulnerability has been resolved: ibmasm: fix heap over-read in ibmasm_send_i2o_message() The ibmasm_send_i2o_message() function uses get_dot_command_size() to compute the byte count for memcpy_toio(), but this value is derived from user-controlled fields in the dot_command_header (command_size: u8, data_size: u16) and is never validated against the actual allocation size. A root user can write a small buffer with inflated header fields, causing memcpy_toio() to read up to ~65 KB past the end of the allocation into adjacent kernel heap, which is then forwarded to the service processor over MMIO. Silently clamping the copy size is not sufficient: if the header fields claim a larger size than the buffer, the SP receives a dot command whose own header is inconsistent with the I2O message length, which can cause the SP to desynchronize. Reject such commands outright by returning failure. Validate command_size before calling get_mfa_inbound() to avoid leaking an I2O message frame: reading INBOUND_QUEUE_PORT dequeues a hardware frame from the controller's free pool, and returning without a corresponding set_mfa_inbound() call would permanently exhaust it. Additionally, clamp command_size to I2O_COMMAND_SIZE before the memcpy_toio() so the MMIO write stays within the I2O message frame, consistent with the clamping already performed by outgoing_message_size() for the header field.

CVSS Metrics

Base Score: 7.1 (HIGH)

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

Attack VectorLOCAL
Attack ComplexityLOW
Privileges RequiredLOW
User InteractionNONE
ScopeUNCHANGED
Confidentiality ImpactHIGH
Integrity ImpactNONE
Availability ImpactHIGH

Source: [email protected]

Type: Primary

Exploitability Score: 1.8

Impact Score: 5.2

Weaknesses

Source Type Description
[email protected] Primary
en CWE-125

Affected Products

Vendor Product Version Update Type
linux linux_kernel * <built-in method update of dict object at 0x7fd2dbc08f00> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7fd384e28180> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7fd2a0507580> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7fd289fbbc80> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7fd2dbc09d00> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7fd384e2b9c0> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7fd30868a080> Operating System
linux linux_kernel 2.6.12 <built-in method update of dict object at 0x7fd289fb95c0> Operating System
linux linux_kernel 2.6.12 <built-in method update of dict object at 0x7fd360692240> Operating System
linux linux_kernel 2.6.12 <built-in method update of dict object at 0x7fd2dbc0acc0> Operating System
linux linux_kernel 2.6.12 <built-in method update of dict object at 0x7fd34011ee40> Operating System
linux linux_kernel 2.6.12 <built-in method update of dict object at 0x7fd384e2bbc0> Operating System

Affected Configurations

Operator: OR

Vulnerable CPE
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:2.6.12:-:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:2.6.12:rc2:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:2.6.12:rc3:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:2.6.12:rc4:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:2.6.12:rc5:*:*:*:*:*:*

References