{"id":"CVE-2023-4809","state":"PUBLISHED","title":"pf incorrectly handles multiple IPv6 fragment headers","description":"In pf packet processing with a 'scrub fragment reassemble' rule, a packet containing multiple IPv6 fragment headers would be reassembled, and then immediately processed.  That is, a packet with multiple fragment extension headers would not be recognized as the correct ultimate payload. Instead a packet with multiple IPv6 fragment headers would unexpectedly be interpreted as a fragmented packet, rather than as whatever the real payload is.\n\n\n\n\nAs a result, IPv6 fragments may bypass pf firewall rules written on the assumption all fragments have been reassembled and, as a result, be forwarded or processed by the host.","publishedAt":"2023-09-06T19:26:45.833Z","updatedAt":"2025-02-13T17:18:10.982Z","severity":null,"assigner":"freebsd","products":["FreeBSD FreeBSD"],"affected":[{"vendor":"FreeBSD","product":"FreeBSD","defaultStatus":"unknown","versions":[{"version":"13.2-RELEASE","status":"affected","lessThan":"p3","versionType":"release"},{"version":"12.4-RELEASE","status":"affected","lessThan":"p5","versionType":"release"}],"modules":["pf"]}],"references":["https://security.FreeBSD.org/advisories/FreeBSD-SA-23:10.pf.asc","http://www.openwall.com/lists/oss-security/2023/09/08/5","http://www.openwall.com/lists/oss-security/2023/09/08/6","http://www.openwall.com/lists/oss-security/2023/09/08/7","https://security.netapp.com/advisory/ntap-20231221-0009/"],"weaknesses":["CWE-167"],"ingestedAt":"2026-10-29T20:06:33.064Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2023/4xxx/CVE-2023-4809.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.1","cveMetadata":{"cveId":"CVE-2023-4809","state":"PUBLISHED","datePublished":"2023-09-06T19:26:45.833Z","dateUpdated":"2025-02-13T17:18:10.982Z","assignerShortName":"freebsd","assignerOrgId":"63664ac6-956c-4cba-a5d0-f46076e16109","dateReserved":"2023-09-06T17:11:30.349Z"},"containers":{"cna":{"title":"pf incorrectly handles multiple IPv6 fragment headers","descriptions":[{"lang":"en","value":"In pf packet processing with a 'scrub fragment reassemble' rule, a packet containing multiple IPv6 fragment headers would be reassembled, and then immediately processed.  That is, a packet with multiple fragment extension headers would not be recognized as the correct ultimate payload. Instead a packet with multiple IPv6 fragment headers would unexpectedly be interpreted as a fragmented packet, rather than as whatever the real payload is.\n\n\n\n\nAs a result, IPv6 fragments may bypass pf firewall rules written on the assumption all fragments have been reassembled and, as a result, be forwarded or processed by the host."}],"affected":[{"vendor":"FreeBSD","product":"FreeBSD","defaultStatus":"unknown","versions":[{"version":"13.2-RELEASE","status":"affected","lessThan":"p3","versionType":"release"},{"version":"12.4-RELEASE","status":"affected","lessThan":"p5","versionType":"release"}],"modules":["pf"]}],"references":[{"url":"https://security.FreeBSD.org/advisories/FreeBSD-SA-23:10.pf.asc","tags":["vendor-advisory"]},{"url":"http://www.openwall.com/lists/oss-security/2023/09/08/5"},{"url":"http://www.openwall.com/lists/oss-security/2023/09/08/6"},{"url":"http://www.openwall.com/lists/oss-security/2023/09/08/7"},{"url":"https://security.netapp.com/advisory/ntap-20231221-0009/"}],"problemTypes":[{"descriptions":[{"cweId":"CWE-167","description":"CWE-167: Improper Handling of Additional Special Element","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"freebsd","orgId":"63664ac6-956c-4cba-a5d0-f46076e16109","dateUpdated":"2023-12-21T22:06:15.441Z"},"credits":[{"lang":"en","type":"finder","user":"00000000-0000-4000-9000-000000000000","value":"Enrico Bassetti bassetti@di.uniroma1.it (NetSecurityLab @ Sapienza University of Rome)"}],"source":{"discovery":"UNKNOWN"},"x_generator":{"engine":"Vulnogram 0.1.0-dev"}},"adp":[{"title":"CVE Program Container","references":[{"url":"https://security.FreeBSD.org/advisories/FreeBSD-SA-23:10.pf.asc","tags":["vendor-advisory","x_transferred"]},{"url":"http://www.openwall.com/lists/oss-security/2023/09/08/5","tags":["x_transferred"]},{"url":"http://www.openwall.com/lists/oss-security/2023/09/08/6","tags":["x_transferred"]},{"url":"http://www.openwall.com/lists/oss-security/2023/09/08/7","tags":["x_transferred"]},{"url":"https://security.netapp.com/advisory/ntap-20231221-0009/","tags":["x_transferred"]}],"providerMetadata":{"shortName":"CVE","orgId":"af854a3a-2127-422b-91ae-364da2661108","dateUpdated":"2024-08-02T07:38:00.699Z"}}]}}}