on control (sysctl) facility in BSD based operating systems OpenBSD 2.2 and earlier, and FreeBSD 2.2.5 and earlier, does not properly restrict source routed packets even when the (1) dosourceroute or (2) forwarding variables are set, which allows remote attackers to spoof TCP connections. NIST National Vulnerability Database (NVD) -- services.nvd.nist.gov (CVE / CVSS / CPE). {"cve":{"id":"CVE-1999-0305","sourceIdentifier":"cve@mitre.org","published":"1998-02-01T05:00:00.000","lastModified":"2026-06-16T21:48:06.863","vulnStatus":"Modified","cveTags":[],"descriptions":[{"lang":"en","value":"The system configuration control (sysctl) facility in BSD based operating systems OpenBSD 2.2 and earlier, and FreeBSD 2.2.5 and earlier, does not properly restrict source routed packets even when the (1) dosourceroute or (2) forwarding variables are set, which allows remote attackers to spoof TCP connections."}],"affected":[{"source":"cve@mitre.org","affectedData":[{"vendor":"n/a","product":"n/a","versions":[{"version":"n/a","status":"affected"}]}]}],"metrics":{"cvssMetricV2":[{"source":"nvd@nist.gov","type":"Primary","cvssData":{"version":"2.0","vectorString":"AV:N/AC:L/Au:N/C:P/I:N/A:N","baseScore":5.0,"accessVector":"NETWORK","accessComplexity":"LOW","authentication":"NONE","confidentialityImpact":"PARTIAL","integrityImpact":"NONE","availabilityImpact":"NONE"},"baseSeverity":"MEDIUM","exploitabilityScore":10.0,"impactScore":2.9,"acInsufInfo":false,"obtainAllPrivilege":false,"obtainUserPrivilege":false,"obtainOtherPrivilege":false,"userInteractionRequired":false}]},"weaknesses":[{"source":"nvd@nist.gov","type":"Primary","description":[{"lang":"en","value":"NVD-CWE-Other"}]}],"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:bsdi:bsd_os:*:*:*:*:*:*:*:*","matchCriteriaId":"CA7932DF-A035-4506-9BF1-C733DC5DD872"},{"vulnerable":true,"criteria":"cpe:2.3:o:freebsd:freebsd:2.2:*:*:*:*:*:*:*","matchCriteriaId":"183667CA-6DF1-4BFB-AE32-9ABF55B7283A"},{"vulnerable":true,"criteria":"cpe:2.3:o:freebsd:freebsd:2.2.5:*:*:*:*:*:*:*","matchCriteriaId":"314BA420-4C74-4060-8ACE-D7A7C041CF2B"},{"vulnerable":true,"criteria":"cpe:2.3:o:openbsd:openbsd:2.0:*:*:*:*:*:*:*","matchCriteriaId":"36DF0D51-FCFA-46A3-B834-E80DFA91DFDC"},{"vulnerable":true,"criteria":"cpe:2.3:o:openbsd:openbsd:2.1:*:*:*:*:*:*:*","matchCriteriaId":"5CB726CF-ADA2-4CDA-9786-1E84AC53740A"},{"vulnerable":true,"criteria":"cpe:2.3:o:openbsd:openbsd:2.2:*:*:*:*:*:*:*","matchCriteriaId":"1FC373FC-88AC-4B6D-A289-51881ACD57F7"}]}]}],"references":[{"url":"http://www.openbsd.org/advisories/sourceroute.txt","source":"cve@mitre.org"},{"url":"http://www.osvdb.org/11502","source":"cve@mitre.org"},{"url":"https://exchange.xforce.ibmcloud.com/vulnerabilities/736","source":"cve@mitre.org"},{"url":"http://www.openbsd.org/advisories/sourceroute.txt","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.osvdb.org/11502","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://exchange.xforce.ibmcloud.com/vulnerabilities/736","source":"af854a3a-2127-422b-91ae-364da2661108"}]}},