{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2025-68206", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2025-68206", "idYear": 2025, "status": "PUBLISHED", "publishedAt": "2025-12-16T13:48:33.763Z", "updatedAt": "2026-10-15T22:02:47.582Z", "importedAt": "2026-10-24T01:57:44.935Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "netfilter: nft_ct: add seqadj extension for natted connections", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nft_ct: add seqadj extension for natted connections\n\nSequence adjustment may be required for FTP traffic with PASV/EPSV modes.\ndue to need to re-write packet payload (IP, port) on the ftp control\nconnection. This can require changes to the TCP length and expected\nseq / ack_seq.\n\nThe easiest way to reproduce this issue is with PASV mode.\nExample ruleset:\ntable inet ftp_nat {\n ct helper ftp_helper {\n type \"ftp\" protocol tcp\n l3proto inet\n }\n\n chain prerouting {\n type filter hook prerouting priority 0; policy accept;\n tcp dport 21 ct state new ct helper set \"ftp_helper\"\n }\n}\ntable ip nat {\n chain prerouting {\n type nat hook prerouting priority -100; policy accept;\n tcp dport 21 dnat ip prefix to ip daddr map {\n\t\t\t192.168.100.1 : 192.168.13.2/32 }\n }\n\n chain postrouting {\n type nat hook postrouting priority 100 ; policy accept;\n tcp sport 21 snat ip prefix to ip saddr map {\n\t\t\t192.168.13.2 : 192.168.100.1/32 }\n }\n}\n\nNote that the ftp helper gets assigned *after* the dnat setup.\n\nThe inverse (nat after helper assign) is handled by an existing\ncheck in nf_nat_setup_info() and will not show the problem.\n\nTopoloy:\n\n +-------------------+ +----------------------------------+\n | FTP: 192.168.13.2 | <-> | NAT: 192.168.13.3, 192.168.100.1 |\n +-------------------+ +----------------------------------+\n |\n +-----------------------+\n | Client: 192.168.100.2 |\n +-----------------------+\n\nftp nat changes do not work as expected in this case:\nConnected to 192.168.100.1.\n[..]\nftp> epsv\nEPSV/EPRT on IPv4 off.\nftp> ls\n227 Entering passive mode (192,168,100,1,209,129).\n421 Service not available, remote server has closed connection.\n\nKernel logs:\nMissing nfct_seqadj_ext_add() setup call\nWARNING: CPU: 1 PID: 0 at net/netfilter/nf_conntrack_seqadj.c:41\n[..]\n __nf_nat_mangle_tcp_packet+0x100/0x160 [nf_nat]\n nf_nat_ftp+0x142/0x280 [nf_nat_ftp]\n help+0x4d1/0x880 [nf_conntrack_ftp]\n nf_confirm+0x122/0x2e0 [nf_conntrack]\n nf_hook_slow+0x3c/0xb0\n ..\n\nFix this by adding the required extension when a conntrack helper is assigned\nto a connection that has a nat binding.", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "1a64edf54f55d7956cf5a0d95898bc1f84f9b818", "status": "affected", "versionType": "git", "lessThan": "83273af0b60c093ba0085c205864d8542e1b1653" }, { "version": "1a64edf54f55d7956cf5a0d95898bc1f84f9b818", "status": "affected", "versionType": "git", "lessThan": "b19492c25eff04852e0cb58f9bb8238b6695ed2d" }, { "version": "1a64edf54f55d7956cf5a0d95898bc1f84f9b818", "status": "affected", "versionType": "git", "lessThan": "4de80f0dc3868408dd7fe9817e507123c9dd8bb0" }, { "version": "1a64edf54f55d7956cf5a0d95898bc1f84f9b818", "status": "affected", "versionType": "git", "lessThan": "b477ef7fa612fa45b6b3134d90d1eeb09396500a" }, { "version": "1a64edf54f55d7956cf5a0d95898bc1f84f9b818", "status": "affected", "versionType": "git", "lessThan": "4ab2cd906e4e1a19ddbda6eb532851b0e9cda110" }, { "version": "1a64edf54f55d7956cf5a0d95898bc1f84f9b818", "status": "affected", "versionType": "git", "lessThan": "2b52d89cbbb0dbe3e948d8d9a91e704316dccfe6" }, { "version": "1a64edf54f55d7956cf5a0d95898bc1f84f9b818", "status": "affected", "versionType": "git", "lessThan": "90918e3b6404c2a37837b8f11692471b4c512de2" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "4.12", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "4.12" }, { "version": "5.10.253", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.10.*" }, { "version": "5.15.203", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "6.1.167", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.6.130", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.12.64", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.12.*" }, { "version": "6.17.9", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.17.*" }, { "version": "6.18", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }