CVE-2024-47685: netfilter: nf_reject_ipv6: fix nf_reject_ip6_tcphdr_put()
Vulnerability summary
CVE-2024-47685 is a critical (CVSS 9.1) Use of Uninitialized Resource vulnerability in debian debian_linux. EPSS estimates a 1.36% chance of exploitation in the next 30 days, higher than 71.7% of scored vulnerabilities.
Severe, CVSS 9.1 (NVD); no exploitation reported by the 5 checked sources; EPSS 1% (FIRST, 03-11-2026)
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 59 · Related 54Timeline
- 21-10-2024PublishedVulnerability first disclosed.
- 15-10-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_reject_ipv6: fix nf_reject_ip6_tcphdr_put() syzbot reported that nf_reject_ip6_tcphdr_put() was possibly sending garbage on the four reserved tcp bits (th->res1) Use skb_put_zero() to clear the whole TCP header, as done in nf_reject_ip_tcphdr_put() BUG: KMSAN: uninit-value in nf_reject_ip6_tcphdr_put+0x688/0x6c0 net/ipv6/netfilter/nf_reject_ipv6.c:255 nf_reject_ip6_tcphdr_put+0x688/0x6c0 net/ipv6/netfilter/nf_reject_ipv6.c:255 nf_send_reset6+0xd84/0x15b0 net/ipv6/netfilter/nf_reject_ipv6.c:344 nft_reject_inet_eval+0x3c1/0x880 net/netfilter/nft_reject_inet.c:48 expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline] nft_do_chain+0x438/0x22a0 net/netfilter/nf_tables_core.c:288 nft_do_chain_inet+0x41a/0x4f0 net/netfilter/nft_chain_filter.c:161 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xf4/0x400 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK include/linux/netfilter.h:312 [inline] ipv6_rcv+0x29b/0x390 net/ipv6/ip6_input.c:310 __netif_receive_skb_one_core net/core/dev.c:5661 [inline] __netif_receive_skb+0x1da/0xa00 net/core/dev.c:5775 process_backlog+0x4ad/0xa50 net/core/dev.c:6108 __napi_poll+0xe7/0x980 net/core/dev.c:6772 napi_poll net/core/dev.c:6841 [inline] net_rx_action+0xa5a/0x19b0 net/core/dev.c:6963 handle_softirqs+0x1ce/0x800 kernel/softirq.c:554 __do_softirq+0x14/0x1a kernel/softirq.c:588 do_softirq+0x9a/0x100 kernel/softirq.c:455 __local_bh_enable_ip+0x9f/0xb0 kernel/softirq.c:382 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:908 [inline] __dev_queue_xmit+0x2692/0x5610 net/core/dev.c:4450 dev_queue_xmit include/linux/netdevice.h:3105 [inline] neigh_resolve_output+0x9ca/0xae0 net/core/neighbour.c:1565 neigh_output include/net/neighbour.h:542 [inline] ip6_finish_output2+0x2347/0x2ba0 net/ipv6/ip6_output.c:141 __ip6_finish_output net/ipv6/ip6_output.c:215 [inline] ip6_finish_output+0xbb8/0x14b0 net/ipv6/ip6_output.c:226 NF_HOOK_COND include/linux/netfilter.h:303 [inline] ip6_output+0x356/0x620 net/ipv6/ip6_output.c:247 dst_output include/net/dst.h:450 [inline] NF_HOOK include/linux/netfilter.h:314 [inline] ip6_xmit+0x1ba6/0x25d0 net/ipv6/ip6_output.c:366 inet6_csk_xmit+0x442/0x530 net/ipv6/inet6_connection_sock.c:135 __tcp_transmit_skb+0x3b07/0x4880 net/ipv4/tcp_output.c:1466 tcp_transmit_skb net/ipv4/tcp_output.c:1484 [inline] tcp_connect+0x35b6/0x7130 net/ipv4/tcp_output.c:4143 tcp_v6_connect+0x1bcc/0x1e40 net/ipv6/tcp_ipv6.c:333 __inet_stream_connect+0x2ef/0x1730 net/ipv4/af_inet.c:679 inet_stream_connect+0x6a/0xd0 net/ipv4/af_inet.c:750 __sys_connect_file net/socket.c:2061 [inline] __sys_connect+0x606/0x690 net/socket.c:2078 __do_sys_connect net/socket.c:2088 [inline] __se_sys_connect net/socket.c:2085 [inline] __x64_sys_connect+0x91/0xe0 net/socket.c:2085 x64_sys_call+0x27a5/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:43 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Uninit was stored to memory at: nf_reject_ip6_tcphdr_put+0x60c/0x6c0 net/ipv6/netfilter/nf_reject_ipv6.c:249 nf_send_reset6+0xd84/0x15b0 net/ipv6/netfilter/nf_reject_ipv6.c:344 nft_reject_inet_eval+0x3c1/0x880 net/netfilter/nft_reject_inet.c:48 expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline] nft_do_chain+0x438/0x22a0 net/netfilter/nf_tables_core.c:288 nft_do_chain_inet+0x41a/0x4f0 net/netfilter/nft_chain_filter.c:161 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xf4/0x400 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK include/linux/netfilter.h:312 [inline] ipv6_rcv+0x29b/0x390 net/ipv6/ip6_input.c:310 __netif_receive_skb_one_core ---truncated---
CVSS metrics
3 scores · 3 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated9.1CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
- OSV · DebianEcosystem advisory · calculated9.1CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
EPSS trend
Probability
1.36%
Chance of exploitation in the next 30 days
Percentile
72%
Versus all other CVEs
30-day change
Decrease -0.01 pp
From 1.37% on 04-10-2026
Known exploited
Compare KEV catalogsNot in the CISA KEV catalog.
Not in the ENISA CNW catalog.
Not in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu134 products
- linux< 4.4.0-272.306 | < 4.15.0-241.253 | < 5.4.0-208.228 | < 5.15.0-127.137 | < 6.8.0-54.56
- linux-allwinner-5.19All versions (No fix recorded)
- linux-aws< 4.4.0-1147.153 | < 4.4.0-1185.200 | < 4.15.0-1184.197 | < 5.4.0-1140.150 | < 5.15.0-1073.79 | < 6.8.0-1023.25
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Debian2 products
- linux< 6.1.115-1 | < 6.11.2-1
- debian_linuxEOL11.0
Linux2 products
- linux≥ c8d7b98bec43faaa6583c3135030be5eb4693acb, < 872eca64c3267dbc5836b715716fc6c03a18eda7 | ≥ c8d7b98bec43faaa6583c3135030be5eb4693acb, < 7bcbc4cda777d26c88500d973fad0d497fc8a82e | ≥ c8d7b98bec43faaa6583c3135030be5eb4693acb, < dcf48ab3ca2c55b09c8f9c8de0df01c1943bc4e5 | ≥ c8d7b98bec43faaa6583c3135030be5eb4693acb, < fbff87d682e57ddbbe82abf6d0a1a4a36a98afcd | ≥ c8d7b98bec43faaa6583c3135030be5eb4693acb, < 7ea2bcfd9bf4c3dbbf22546162226fd1c14d8ad2 | ≥ c8d7b98bec43faaa6583c3135030be5eb4693acb, < af4b8a704f26f38310655bad67fd8096293275a2 | ≥ c8d7b98bec43faaa6583c3135030be5eb4693acb, < 7a7b5a27c53b55e91eecf646d1b204e73fa4af93 | ≥ c8d7b98bec43faaa6583c3135030be5eb4693acb, < 10210658f827ad45061581cbfc05924b723e8922 | ≥ c8d7b98bec43faaa6583c3135030be5eb4693acb, < 9c778fe48d20ef362047e3376dee56d77f8500d4 | 3.18
- linux_kernel≥ 3.18, < 4.19.323 | ≥ 4.20, < 5.4.285 | ≥ 5.5, < 5.10.227 | ≥ 5.11, < 5.15.168 | ≥ 5.16, < 6.1.113 | ≥ 6.2, < 6.6.54 | ≥ 6.7, < 6.10.13 | ≥ 6.11, < 6.11.2
3 vendors · 138 products