CVE-2026-45994
In the Linux kernel, the following vulnerability has been resolved: ibmasm: fix OOB reads in command_file_write due to missing size checks The command_file_write() handler allocates a kernel buffer of exactly count bytes and copies user data into it,…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.14%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
In the Linux kernel, the following vulnerability has been resolved: ibmasm: fix OOB reads in command_file_write due to missing size checks The command_file_write() handler allocates a kernel buffer of exactly count bytes and copies user data into it, but does not validate the buffer against the dot command protocol before passing it to get_dot_command_size() and get_dot_command_timeout(). Since both the allocation size (count) and the header fields (command_size, data_size) are independently user-controlled, an attacker can cause get_dot_command_size() to return a value exceeding the allocation, triggering OOB reads in get_dot_command_timeout() and an out-of-bounds memcpy_toio() that leaks kernel heap memory to the service processor. Fix with two guards: reject writes smaller than sizeof(struct dot_command_header) before allocation, then after copying user data reject commands where the buffer is smaller than the total size declared by the header (sizeof(header) + command_size + data_size). This ensures all subsequent header and payload field accesses stay within the buffer.
- CVSS 3.1
- 7.1 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
- EPSS
- 0.14% probability · 4th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-125
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/0eb09f737428e482a32a2e31e5e223f2b35a71d3Patch
- https://git.kernel.org/stable/c/44ee19422aa82a6847594866de7e5a31e4ef98b3Patch
- https://git.kernel.org/stable/c/7b8a574da5d7ea99b943f7a3458a17a1d95e8838Patch
- https://git.kernel.org/stable/c/a672682d39dd34e2b5ba4feb436723bed65125ffPatch
- https://git.kernel.org/stable/c/aefc1a97da17d8309974690c8a03e439a91ebb1cPatch
- https://git.kernel.org/stable/c/d0fb4d1dc43f8d5179917a2daaa82680993d4cdfPatch
- https://git.kernel.org/stable/c/d50e2019c9d7c433f56d9dff65703eb904aa1fb1Patch
- https://git.kernel.org/stable/c/ee5737891464030a189837467df3b81a273718adPatch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.