CVE-2026-43384

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Use the appropriate helper function for this."}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL"}, "scenarios": [{"lang": "en", "value": "AV:N - The vulnerable comparison is reached by inbound IPv4/IPv6 TCP packets carrying a TCP-AO option, before normal TCP processing of the segment.\nAC:L - The attacker controls the candidate MAC bytes and can send repeated chosen packets to average timing differences; no race or condition outside the attacker\u2019s control is required once a TCP-AO-protected socket is reachable.\nPR:N - The vulnerable path is the TCP-AO authentication check itself, so the attacker does not need the AO key or any local privilege before sending probes.\nUI:N - No victim user action is required; packet receipt by the configured TCP-AO endpoint is sufficient.\nS:U - The impact remains within the kernel/network endpoint and the TCP sessions protected by that endpoint, with no VM, sandbox, or separate security-authority escape.\nC:H - A successful MAC-forgery timing attack can let an unauthenticated network attacker impersonate a trusted TCP-AO peer and receive data made available to that authenticated peer.\nI:H - Forged valid TCP-AO segments can inject or alter arbitrary TCP stream/control data for protected connections, defeating the integrity guarantee TCP-AO is meant to provide.\nA:H - Forged valid TCP-AO control segments such as RST/FIN or malicious stream data can tear down or disrupt protected long-lived sessions such as routing/control-plane connections."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/ipv4/Kconfig", "net/ipv4/tcp_ao.c"], "versions": [{"version": "0a3a809089eb1d4a0a2fd0c16b520d603988c859", "lessThan": "8be6ed64966da48b6c4726918f106c18742a5125", "status": "affected", "versionType": "git"}, {"version": "0a3a809089eb1d4a0a2fd0c16b520d603988c859", "lessThan": "a269cbdc442f8658bca35383e34b9d0b0ff95a1c", "status": "affected", "versionType": "git"}, {"version": "0a3a809089eb1d4a0a2fd0c16b520d603988c859", "lessThan": "080b0e210088296dd50d6637c06c1db14246adfe", "status": "affected", "versionType": "git"}, {"version": "0a3a809089eb1d4a0a2fd0c16b520d603988c859", "lessThan": "67edfec516d30d3e62925c397be4a1e5185802fc", "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/ipv4/Kconfig", "net/ipv4/tcp_ao.c"], "versions": [{"version": "6.7", "status": "affected"}, {"version": "0", "lessThan": "6.7", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.78", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.19", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.19.9", "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:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "6.12.78"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "6.18.19"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "6.19.9"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "7.0"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/8be6ed64966da48b6c4726918f106c18742a5125"}, {"url": "https://git.kernel.org/stable/c/a269cbdc442f8658bca35383e34b9d0b0ff95a1c"}, {"url": "https://git.kernel.org/stable/c/080b0e210088296dd50d6637c06c1db14246adfe"}, {"url": "https://git.kernel.org/stable/c/67edfec516d30d3e62925c397be4a1e5185802fc"}], "title": "net/tcp-ao: Fix MAC comparison to be constant-time", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

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{"bugzilla": {"description": "kernel: net/tcp-ao: Fix MAC comparison to be constant-time", "id": "2468142", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2468142"}, "csaw": false, "cwe": "CWE-208", "details": ["A flaw was found in the Linux kernel's TCP Authentication Option (TCP-AO) implementation. This vulnerability arises from a non-constant-time comparison of Message Authentication Codes (MACs). A remote attacker could potentially exploit this timing discrepancy to perform a timing attack, which may lead to the disclosure of sensitive information."], "name": "CVE-2026-43384", "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"}], "public_date": "2026-05-08T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-43384\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-43384\nhttps://lore.kernel.org/linux-cve-announce/2026050834-CVE-2026-43384-d8ea@gregkh/T"]}

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