CVE-2026-89743
misc: nsm: bound the device-reported response length
Description
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.
INFO
Published Date :
Sept. 11, 2026, 8:20 p.m.
Last Modified :
Sept. 11, 2026, 8:20 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products
The following products are affected by CVE-2026-89743
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
Solution
- Apply kernel patch to bound response length.
- Ensure response length does not exceed buffer size.
- Update kernel to latest version.
- Validate kernel changes.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-89743.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-89743 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-89743
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-89743 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-89743 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Sep. 11, 2026
Action Type Old Value New Value Added Description 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. Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/89xxx/CVE-2026-89743.json">CVE-2026-89743</a> Added Reference https://git.kernel.org/stable/c/29e634a18957acda11383a15ab98a91c4ae9e294 Added Reference https://git.kernel.org/stable/c/2aa0fb9c96f894a9c179a48e7522ea6705800adf Added Reference https://git.kernel.org/stable/c/339f19b9a6171289b0e797deb8bda80b9a1fcc30 Added Reference https://git.kernel.org/stable/c/808e530654a5354e6df78863a5d61e4d44e67235