{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-43190", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-05-01T14:12:55.992Z", "datePublished": "2026-05-06T11:27:59.798Z", "dateUpdated": "2026-05-06T11:27:59.798Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-05-06T11:27:59.798Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: xt_tcpmss: check remaining length before reading optlen\n\nQuoting reporter:\n In net/netfilter/xt_tcpmss.c (lines 53-68), the TCP option parser reads\n op[i+1] directly without validating the remaining option length.\n\n If the last byte of the option field is not EOL/NOP (0/1), the code attempts\n to index op[i+1]. In the case where i + 1 == optlen, this causes an\n out-of-bounds read, accessing memory past the optlen boundary\n (either reading beyond the stack buffer _opt or the\n following payload)."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/netfilter/xt_tcpmss.c"], "versions": [{"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "f895191dc32c53eaf443b6443fe40945b2f92287", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "cd5beda7e0e32865e214f28034bb92c1cecff885", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "eaedc0bc18be46fe7f58170e967959a932c4f824", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "07a9b32eaae792ff7d0fcac14d8920c937c0a9c3", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "8b300f726640c48c3edfe9c453334dd801f4b74e", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "5e13d0a37666955b6cfddc0f73cb40ed645b8a05", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "f6c412dcfd76b0516d51aa847d8f4c7b70381b09", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "735ee8582da3d239eb0c7a53adca61b79fb228b3", "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/netfilter/xt_tcpmss.c"], "versions": [{"version": "5.10.252", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.15.202", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.165", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.128", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.75", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.16", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.19.6", "lessThanOrEqual": "6.19.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.0", "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:*:*:*:*:*:*:*:*", "versionEndExcluding": "5.10.252"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "5.15.202"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.1.165"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.6.128"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.12.75"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.18.16"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.19.6"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "7.0"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/f895191dc32c53eaf443b6443fe40945b2f92287"}, {"url": "https://git.kernel.org/stable/c/cd5beda7e0e32865e214f28034bb92c1cecff885"}, {"url": "https://git.kernel.org/stable/c/eaedc0bc18be46fe7f58170e967959a932c4f824"}, {"url": "https://git.kernel.org/stable/c/07a9b32eaae792ff7d0fcac14d8920c937c0a9c3"}, {"url": "https://git.kernel.org/stable/c/8b300f726640c48c3edfe9c453334dd801f4b74e"}, {"url": "https://git.kernel.org/stable/c/5e13d0a37666955b6cfddc0f73cb40ed645b8a05"}, {"url": "https://git.kernel.org/stable/c/f6c412dcfd76b0516d51aa847d8f4c7b70381b09"}, {"url": "https://git.kernel.org/stable/c/735ee8582da3d239eb0c7a53adca61b79fb228b3"}], "title": "netfilter: xt_tcpmss: check remaining length before reading optlen", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: xt_tcpmss: check remaining length before reading optlen\n\nQuoting reporter:\n In net/netfilter/xt_tcpmss.c (lines 53-68), the TCP option parser reads\n op[i+1] directly without validating the remaining option length.\n\n If the last byte of the option field is not EOL/NOP (0/1), the code attempts\n to index op[i+1]. In the case where i + 1 == optlen, this causes an\n out-of-bounds read, accessing memory past the optlen boundary\n (either reading beyond the stack buffer _opt or the\n following payload)."}], "id": "CVE-2026-43190", "lastModified": "2026-05-06T13:07:51.607", "metrics": {}, "published": "2026-05-06T12:16:37.843", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/07a9b32eaae792ff7d0fcac14d8920c937c0a9c3"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/5e13d0a37666955b6cfddc0f73cb40ed645b8a05"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/735ee8582da3d239eb0c7a53adca61b79fb228b3"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/8b300f726640c48c3edfe9c453334dd801f4b74e"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/cd5beda7e0e32865e214f28034bb92c1cecff885"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/eaedc0bc18be46fe7f58170e967959a932c4f824"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/f6c412dcfd76b0516d51aa847d8f4c7b70381b09"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/f895191dc32c53eaf443b6443fe40945b2f92287"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Awaiting Analysis"}

{"bugzilla": {"description": "kernel: netfilter: xt_tcpmss: check remaining length before reading optlen", "id": "2467064", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2467064"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.0", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "status": "draft"}, "cwe": "CWE-130", "details": ["A flaw was found in the Linux kernel, specifically within the netfilter: xt_tcpmss module. A remote attacker could exploit this vulnerability by sending a specially crafted TCP packet. The TCP option parser does not properly validate the remaining option length, which results in an out-of-bounds read. This allows an attacker to access memory beyond the intended buffer, potentially leading to information disclosure."], "name": "CVE-2026-43190", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Under investigation", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-05-06T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-43190\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-43190\nhttps://lore.kernel.org/linux-cve-announce/2026050642-CVE-2026-43190-f1c9@gregkh/T"], "threat_severity": "Important"}