Homepage

CVE-2025-68206 Affecting kernel-docs-html package, versions <6.12.0-160000.9.1

Severity

 Recommended
0.0
medium
0
10

Based on SUSE Linux Enterprise Server security rating.

Threat Intelligence

EPSS
0.03% (9th percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-SLES1600-KERNELDOCSHTML-15242467
  • published6 Feb 2026
  • disclosed2 Feb 2026
Report a new vulnerability Found a mistake?

Introduced: 2 Feb 2026

NewCVE-2025-68206  (opens in a new tab)

How to fix?

Upgrade SLES:16.0.0 kernel-docs-html to version 6.12.0-160000.9.1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream kernel-docs-html package and not the kernel-docs-html package as distributed by SLES. See How to fix? for SLES:16.0.0 relevant fixed versions and status.

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 &#34;ftp_helper&#34;
    }

} 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.

CVSS Base Scores

version 3.1