CVE-2026-89743

Updated on 11 Sep 2026

Severity

7.7 High severity

Details

CVSS score
7.7
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Overview

About vulnerability

In the Linux kernel, the following vulnerability has been resolved:

misc: nsm: bound the device-reported response length

nsm_sendrecv_msg_locked() stores the virtqueue used-ring length reported by the NSM device into msg->resp.len without bounding it to the response buffer. A malicious or buggy backend can report a length larger than the response buffer; parse_resp_raw() then copies that many bytes out of the fixed buffer to user space, disclosing adjacent kernel heap (an out-of-bounds read). The request path already floors its length in fill_req_raw(); the response path lacks the symmetric check.

Clamp the stored length to the size of the response buffer. Well-behaved devices report no more than the posted buffer size, so conforming traffic is unaffected.

Details

Affected product:
Debian 10 ELS , Debian 11 ELS
Affected packages:
linux @ 5.10.259 (+1 more)

Fixes