{"cve":"CVE-2026-93186","nvd":{"published":"2026-09-17T17:18:14.683","modified":"2026-10-21T13:21:02.487","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ncxl/mbox: Clamp mailbox output allocation to the payload size\n\nCXL_MEM_SEND_COMMAND bounds the user's in.size to the mailbox payload\nsize but leaves out.size unbounded, then cxl_mbox_cmd_ctor() calls\nkvzalloc(out.size). A large out.size drives a huge allocation, above\nINT_MAX it WARNs and taints, and with panic_on_warn=1 it panics.\n\nThe transport __cxl_pci_mbox_send_cmd() already clamps the response copy\nto min(out.size, payload_size, device len), so the output buffer is\nnever written beyond payload_size. Clamp the allocation to payload_size\ntoo, matching the RAW path.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["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/d2d40574b9b272ade32d0d77b140d990e7547f5f","https://git.kernel.org/stable/c/f5d2bbf0300f46307948864fbb97bce5097f4fe2"],"products":[],"source":"nvd","synced_at":"2026-10-22T16:41:11.231219466+00:00"},"epss":{"cve":"CVE-2026-93186","score":0.00193,"percentile":0.0893,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}