CVE-2026-98438

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-98438", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.349Z", "datePublished": "2026-10-18T14:45:27.288Z", "dateUpdated": "2026-10-19T09:19:34.132Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T09:19:34.132Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: options: fix uninit-value in mptcp_write_data_fin\n\nWhen sending a DATA_FIN without data, and because the DATA_FIN occupies\n1 octet of the connection-level sequence space [1], it is then required\nto add a DSS mapping with specific values.\n\nIf the checksum has been negotiated, it also needs to be computed, and\nincluded in the outgoing packet, and thus the initial csum data needs to\nbe reset to 0 as well. This is no longer the case since commit\ncfcceb7a39fc (\"tcp: shrink per-packet memset in __tcp_transmit_skb()\"),\nbecause the whole ext_copy structure is no longer zeroed by default.\n\nThis seems to be the only case where use_map is changed and set\nafterwards, so initialising the csum field only in this case, along with\nother fields for this specific case."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/mptcp/options.c"], "versions": [{"version": "cfcceb7a39fc10a6f896af8229bf81d96acb22cc", "lessThan": "9a682067dd7b9dce6b94a0a05661dcc921446402", "status": "affected", "versionType": "git"}, {"version": "cfcceb7a39fc10a6f896af8229bf81d96acb22cc", "lessThan": "b110f1dd6cb6a9930503354a01a315e0a821eaa7", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/mptcp/options.c"], "versions": [{"version": "7.1", "status": "affected"}, {"version": "0", "lessThan": "7.1", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.7", "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": "7.1", "versionEndExcluding": "7.2.7"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.1", "versionEndExcluding": "7.3"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/9a682067dd7b9dce6b94a0a05661dcc921446402"}, {"url": "https://git.kernel.org/stable/c/b110f1dd6cb6a9930503354a01a315e0a821eaa7"}], "title": "mptcp: options: fix uninit-value in mptcp_write_data_fin", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["net/mptcp/options.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "9a682067dd7b9dce6b94a0a05661dcc921446402", "status": "affected", "version": "cfcceb7a39fc10a6f896af8229bf81d96acb22cc", "versionType": "git"}, {"lessThan": "b110f1dd6cb6a9930503354a01a315e0a821eaa7", "status": "affected", "version": "cfcceb7a39fc10a6f896af8229bf81d96acb22cc", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["net/mptcp/options.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "7.1"}, {"lessThan": "7.1", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.7", "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\nmptcp: options: fix uninit-value in mptcp_write_data_fin\n\nWhen sending a DATA_FIN without data, and because the DATA_FIN occupies\n1 octet of the connection-level sequence space [1], it is then required\nto add a DSS mapping with specific values.\n\nIf the checksum has been negotiated, it also needs to be computed, and\nincluded in the outgoing packet, and thus the initial csum data needs to\nbe reset to 0 as well. This is no longer the case since commit\ncfcceb7a39fc (\"tcp: shrink per-packet memset in __tcp_transmit_skb()\"),\nbecause the whole ext_copy structure is no longer zeroed by default.\n\nThis seems to be the only case where use_map is changed and set\nafterwards, so initialising the csum field only in this case, along with\nother fields for this specific case."}], "id": "CVE-2026-98438", "lastModified": "2026-10-19T10:18:51.960", "metrics": {}, "published": "2026-10-18T15:16:53.590", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/9a682067dd7b9dce6b94a0a05661dcc921446402"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/b110f1dd6cb6a9930503354a01a315e0a821eaa7"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: mptcp: options: fix uninit-value in mptcp_write_data_fin", "id": "2554819", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2554819"}, "csaw": false, "cvss3": {"cvss3_base_score": "3.7", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L", "status": "draft"}, "cwe": "CWE-908", "details": ["A flaw was found in the Linux kernel's Multipath TCP (MPTCP) subsystem. When handling connection termination (DATA_FIN) packets without payload data while checksum negotiation is enabled, the kernel fails to properly initialize memory before computing the packet checksum. A network peer could trigger this condition during connection teardown, resulting in corrupted packet headers, dropped packets, or a denial of service."], "name": "CVE-2026-98438", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Not affected", "package_name": "openshift/ose-rhel-coreos-8", "product_name": "Red Hat OpenShift Container Platform 4"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Not affected", "package_name": "openshift/ose-rhel-coreos-9", "product_name": "Red Hat OpenShift Container Platform 4"}], "public_date": "2026-10-18T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-98438\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-98438\nhttps://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98438.mbox"], "threat_severity": "Low"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[cfcceb7a39fc10a6f896af8229bf81d96acb22cc,9a682067dd7b9dce6b94a0a05661dcc921446402)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[cfcceb7a39fc10a6f896af8229bf81d96acb22cc,b110f1dd6cb6a9930503354a01a315e0a821eaa7)"}}], "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": "7.1"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,7.1)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2.7,7.3.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.3-rc3,*]"}}], "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": "2026-10-18T17:30:16.960876+00:00", "updated": "2026-10-19T16:30:13.909469+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}