CVE-2026-93096
cxl/features: Serialize multi-part Get/Set Feature transfers
Description
In the Linux kernel, the following vulnerability has been resolved: cxl/features: Serialize multi-part Get/Set Feature transfers A Get or Set Feature payload larger than the mailbox payload size is split into several mailbox commands. mbox_mutex only serializes individual mailbox commands and is dropped between iterations of these loops. Nothing serializes the multi-part transfer as a whole. cxl_get_feature() and cxl_set_feature() are reachable concurrently from fwctl (per-fd RPCs run under a read-held registration lock) and from the EDAC scrub/ECS/repair paths, so two transfers to the same mailbox can interleave their parts and corrupt the device's transfer context. Add a per-mailbox feat_mutex and hold it across the whole transfer in both functions. It nests outside mbox_mutex (which is taken inside cxl_internal_send_cmd()), and is taken nowhere else, so no lock-ordering inversion is introduced.
INFO
Published Date :
Sept. 17, 2026, 5:18 p.m.
Last Modified :
Sept. 17, 2026, 5:18 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
- Acquire per-mailbox feat_mutex across feature transfers.
- Hold feat_mutex outside mbox_mutex during transfers.
- Ensure mutex nesting does not introduce inversions.
- Apply patches to kernel code handling feature transfers.
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-2026-93096.
| URL | Resource |
|---|---|
| https://git.kernel.org/stable/c/7682b617db1f19bc606b5f1badadcf1e63a87b14 | |
| https://git.kernel.org/stable/c/77b814c1832fde018c30357b4ec3fcdaa91a1c10 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-93096 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-2026-93096
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-2026-93096 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-93096 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. 17, 2026
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: cxl/features: Serialize multi-part Get/Set Feature transfers A Get or Set Feature payload larger than the mailbox payload size is split into several mailbox commands. mbox_mutex only serializes individual mailbox commands and is dropped between iterations of these loops. Nothing serializes the multi-part transfer as a whole. cxl_get_feature() and cxl_set_feature() are reachable concurrently from fwctl (per-fd RPCs run under a read-held registration lock) and from the EDAC scrub/ECS/repair paths, so two transfers to the same mailbox can interleave their parts and corrupt the device's transfer context. Add a per-mailbox feat_mutex and hold it across the whole transfer in both functions. It nests outside mbox_mutex (which is taken inside cxl_internal_send_cmd()), and is taken nowhere else, so no lock-ordering inversion is introduced. Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/93xxx/CVE-2026-93096.json">CVE-2026-93096</a> Added Reference https://git.kernel.org/stable/c/7682b617db1f19bc606b5f1badadcf1e63a87b14 Added Reference https://git.kernel.org/stable/c/77b814c1832fde018c30357b4ec3fcdaa91a1c10