CVE-2025-68206 | netfilter: nft_ct: add seqadj extension for natted connections

In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_ct: add seqadj extension for natted connections Sequence adjustment may be required for FTP traffic with PASV/EPSV modes. due to need to re-write packet payload (IP, port) on the ftp control connection. This can require changes to the TCP length and expected seq / ack_seq. The easiest way to reproduce this issue is with PASV mode. Example ruleset: table inet ftp_nat { ct helper ftp_helper { type "ftp" protocol tcp l3proto inet } chain prerouting { type filter hook prerouting priority 0; policy accept; tcp dport 21 ct state new ct helper set "ftp_helper" } } table ip nat { chain prerouting { type nat hook prerouting priority -100; policy accept; tcp dport 21 dnat ip prefix to ip daddr map { 192.168.100.1 : 192.168.13.2/32 } } chain postrouting { type nat hook postrouting priority 100 ; policy accept; tcp sport 21 snat ip prefix to ip saddr map { 192.168.13.2 : 192.168.100.1/32 } } } Note that the ftp helper gets assigned *after* the dnat setup. The inverse (nat after helper assign) is handled by an existing check in nf_nat_setup_info() and will not show the problem. Topoloy: +-------------------+ +----------------------------------+ | FTP: 192.168.13.2 | <-> | NAT: 192.168.13.3, 192.168.100.1 | +-------------------+ +----------------------------------+ | +-----------------------+ | Client: 192.168.100.2 | +-----------------------+ ftp nat changes do not work as expected in this case: Connected to 192.168.100.1. [..] ftp> epsv EPSV/EPRT on IPv4 off. ftp> ls 227 Entering passive mode (192,168,100,1,209,129). 421 Service not available, remote server has closed connection. Kernel logs: Missing nfct_seqadj_ext_add() setup call WARNING: CPU: 1 PID: 0 at net/netfilter/nf_conntrack_seqadj.c:41 [..] __nf_nat_mangle_tcp_packet+0x100/0x160 [nf_nat] nf_nat_ftp+0x142/0x280 [nf_nat_ftp] help+0x4d1/0x880 [nf_conntrack_ftp] nf_confirm+0x122/0x2e0 [nf_conntrack] nf_hook_slow+0x3c/0xb0 .. Fix this by adding the required extension when a conntrack helper is assigned to a connection that has a nat binding.

公開: 2025-12-16 最終更新: 2026-07-14 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 ソース: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

総合評価: CVE-2025-68206 は低リスク(7.1/100)。悪用される可能性が高い(EPSS 0.17%、7 パーセンタイル) 推奨対応: 総合リスクは低く緊急対応は不要です。通常の保守サイクルでパッチを適用し、CVSS / EPSS が上昇したら優先度を見直してください。

リスクは変動します。再評価に基づき、本ページの表示内容を更新しています。

CVE-2025-68206 の EPSS(Exploit Prediction Scoring System)スコア

EPSS は日次で悪用されやすさの相対度合いを推定します。パーセンタイルは採点済み CVE の中での相対位置(高いほど相対的に深刻)を示します。

# 日付 旧 EPSS スコア 新 EPSS スコア Δ(新 − 旧)
1 2026-06-15 0.07% 0.17% +0.11%
2 2026-05-26 0.05% 0.07% +0.02%
3 2026-05-15 0.05%

EPSS の全履歴 (全 5 件)

CVE-2025-68206 の CVSS(Common Vulnerability Scoring System)指標

この CVE の CVSS 指標。

この CVE のデータセットに CVSS はありません。

CVE-2025-68206 の弱点分類(列挙)

CVE-2025-68206 の GitHub Security Advisory

GHSA-9r97-6c49-v2hf · 深刻度: unknown — In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_ct: add...

CVE-2025-68206 の OS トラッカー

vendor priority summary link
debian not yet assigned CVE-2025-68206 not yet assigned priority: Debian including 2 source packages (linux, linux-6.1), 6 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 6. https://security-tracker.debian.org/tracker/CVE-2025-68206
redhat low https://access.redhat.com/security/cve/CVE-2025-68206
suse medium CVE-2025-68206 severity moderate: SUSE including 404 source package names (13.2-9.1:libsystemd0-254.23-1.1, 13.2-9.1:libudev1-254.23-1.1, …), 763 product×package rows across 122 product lines (Container suse/sl-micro/6.0/baremetal-os-container, Container suse/sl-micro/6.0/base-os-container, … (122 product lines)): Fixed 492, Known Affected 231, First Fixed 25, Known Not Affected 15. https://www.suse.com/security/cve/CVE-2025-68206/
ubuntu medium CVE-2025-68206 medium priority: Ubuntu including 157 source packages (linux, linux-allwinner-5.19, …), 1405 status rows across 9 suites (bionic, focal, jammy, noble, plucky, questing, trusty, upstream, xenial): DNE 1010, ignored 179, released 114, needed 78, pending 13, not-affected 11. https://ubuntu.com/security/CVE-2025-68206

CVE-2025-68206 の影響を受けるソフトウェア/構成

ベンダー 製品 バージョン 生の CPE
linux linux_kernel >= 4.12, < 5.10.253 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 4.12, < 5.15.203 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 4.12, < 6.1.167 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 4.12, < 6.6.130 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 4.12, < 6.12.64 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 4.12, < 6.17.9 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 4.12, < 6.18 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

CVE-2025-68206 の参考情報

cvelogic Threat Intelligence