CVE-2026-93186

In the Linux kernel, the following vulnerability has been resolved: cxl/mbox: Clamp mailbox output allocation to the payload size CXL_MEM_SEND_COMMAND bounds the user's in.size to the mailbox payload size but leaves out.size unbounded, then cxl_mbox_cmd_ctor() calls kvzalloc(out.size). A large out.size drives a huge allocation, above INT_MAX it WARNs and taints, and with panic_on_warn=1 it panics. The transport __cxl_pci_mbox_send_cmd() already clamps the response copy to min(out.size, payload_size, device len), so the output buffer is never written beyond payload_size. Clamp the allocation to payload_size too, matching the RAW path.

CVSS

No CVSS.

References

Link	Resource
https://git.kernel.org/stable/c/31d4841eca7c4b75751ca96d24339e19303337f2
https://git.kernel.org/stable/c/8a13db9f899d149c3aab24abcb668121cfda5a4f
https://git.kernel.org/stable/c/b4e11c731d6bee3b87315e055a1ca417c92dc1fc
https://git.kernel.org/stable/c/f5d2bbf0300f46307948864fbb97bce5097f4fe2

Configurations

No configuration.

History

17 Sep 2026, 17:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-17 17:18

Updated : 2026-09-17 17:18

NVD link : CVE-2026-93186

Mitre link : CVE-2026-93186

CVE.ORG link : CVE-2026-93186

JSON object : View

Products Affected

No product.

CWE

No CWE.

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