CVE-2026-93186

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-93186", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-17T16:02:15.091Z", "datePublished": "2026-09-17T16:12:12.121Z", "dateUpdated": "2026-10-30T12:36:18.449Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-30T12:36:18.449Z"}, "descriptions": [{"lang": "en", "value": "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."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/cxl/core/mbox.c"], "versions": [{"version": "583fa5e71caeb79e04e477e9837e2f7fa53b71e4", "lessThan": "123f6d154253939ce38f0ec0b6d1ba67f870e01f", "status": "affected", "versionType": "git"}, {"version": "583fa5e71caeb79e04e477e9837e2f7fa53b71e4", "lessThan": "d2d40574b9b272ade32d0d77b140d990e7547f5f", "status": "affected", "versionType": "git"}, {"version": "583fa5e71caeb79e04e477e9837e2f7fa53b71e4", "lessThan": "f5d2bbf0300f46307948864fbb97bce5097f4fe2", "status": "affected", "versionType": "git"}, {"version": "583fa5e71caeb79e04e477e9837e2f7fa53b71e4", "lessThan": "31d4841eca7c4b75751ca96d24339e19303337f2", "status": "affected", "versionType": "git"}, {"version": "583fa5e71caeb79e04e477e9837e2f7fa53b71e4", "lessThan": "b4e11c731d6bee3b87315e055a1ca417c92dc1fc", "status": "affected", "versionType": "git"}, {"version": "583fa5e71caeb79e04e477e9837e2f7fa53b71e4", "lessThan": "8a13db9f899d149c3aab24abcb668121cfda5a4f", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/cxl/core/mbox.c"], "versions": [{"version": "5.12", "status": "affected"}, {"version": "0", "lessThan": "5.12", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.191", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.160", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.110", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.52", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.6", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.3", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.12", "versionEndExcluding": "6.1.191"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.12", "versionEndExcluding": "6.6.160"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.12", "versionEndExcluding": "6.12.110"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.12", "versionEndExcluding": "6.18.52"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.12", "versionEndExcluding": "7.2.6"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.12", "versionEndExcluding": "7.3"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/123f6d154253939ce38f0ec0b6d1ba67f870e01f"}, {"url": "https://git.kernel.org/stable/c/d2d40574b9b272ade32d0d77b140d990e7547f5f"}, {"url": "https://git.kernel.org/stable/c/f5d2bbf0300f46307948864fbb97bce5097f4fe2"}, {"url": "https://git.kernel.org/stable/c/31d4841eca7c4b75751ca96d24339e19303337f2"}, {"url": "https://git.kernel.org/stable/c/b4e11c731d6bee3b87315e055a1ca417c92dc1fc"}, {"url": "https://git.kernel.org/stable/c/8a13db9f899d149c3aab24abcb668121cfda5a4f"}], "title": "cxl/mbox: Clamp mailbox output allocation to the payload size", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["drivers/cxl/core/mbox.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "123f6d154253939ce38f0ec0b6d1ba67f870e01f", "status": "affected", "version": "583fa5e71caeb79e04e477e9837e2f7fa53b71e4", "versionType": "git"}, {"lessThan": "d2d40574b9b272ade32d0d77b140d990e7547f5f", "status": "affected", "version": "583fa5e71caeb79e04e477e9837e2f7fa53b71e4", "versionType": "git"}, {"lessThan": "f5d2bbf0300f46307948864fbb97bce5097f4fe2", "status": "affected", "version": "583fa5e71caeb79e04e477e9837e2f7fa53b71e4", "versionType": "git"}, {"lessThan": "31d4841eca7c4b75751ca96d24339e19303337f2", "status": "affected", "version": "583fa5e71caeb79e04e477e9837e2f7fa53b71e4", "versionType": "git"}, {"lessThan": "b4e11c731d6bee3b87315e055a1ca417c92dc1fc", "status": "affected", "version": "583fa5e71caeb79e04e477e9837e2f7fa53b71e4", "versionType": "git"}, {"lessThan": "8a13db9f899d149c3aab24abcb668121cfda5a4f", "status": "affected", "version": "583fa5e71caeb79e04e477e9837e2f7fa53b71e4", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["drivers/cxl/core/mbox.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "5.12"}, {"lessThan": "5.12", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.191", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.160", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.110", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.52", "versionType": "semver"}, {"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.6", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.3", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "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."}], "id": "CVE-2026-93186", "lastModified": "2026-10-30T13:20:59.543", "metrics": {}, "published": "2026-09-17T17:18:14.683", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/123f6d154253939ce38f0ec0b6d1ba67f870e01f"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/31d4841eca7c4b75751ca96d24339e19303337f2"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/8a13db9f899d149c3aab24abcb668121cfda5a4f"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/b4e11c731d6bee3b87315e055a1ca417c92dc1fc"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/d2d40574b9b272ade32d0d77b140d990e7547f5f"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/f5d2bbf0300f46307948864fbb97bce5097f4fe2"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[583fa5e71caeb79e04e477e9837e2f7fa53b71e4,f5d2bbf0300f46307948864fbb97bce5097f4fe2)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[583fa5e71caeb79e04e477e9837e2f7fa53b71e4,31d4841eca7c4b75751ca96d24339e19303337f2)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[583fa5e71caeb79e04e477e9837e2f7fa53b71e4,b4e11c731d6bee3b87315e055a1ca417c92dc1fc)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[583fa5e71caeb79e04e477e9837e2f7fa53b71e4,8a13db9f899d149c3aab24abcb668121cfda5a4f)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "5.12"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,5.12)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.110,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.52,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2.6,7.3.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.3-rc1,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-09-19T08:30:16.933351+00:00", "updated": "2026-09-19T21:30:16.266426+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"], "weaknesses": ["CWE-188"]}