8.2

CVE-2024-27018: netfilter: br_netfilter: skip conntrack input hook for promisc packets

Modified
AliasesUBUNTU-CVE-2024-27018DEBIAN-CVE-2024-27018
Published 01-05-2024Last modified 05-08-2026

Vulnerability summary

CVE-2024-27018 is a high (CVSS 8.2) vulnerability in fedoraproject fedora. EPSS estimates a 0.64% chance of exploitation in the next 30 days, higher than 50.6% of scored vulnerabilities.

Priority
Prioritisesevere

Severe, CVSS 8.2 (CVE.org); no exploitation reported by the 5 checked sources; EPSS 1% (FIRST, 03-11-2026)

Source freshness unavailable

How is this decided?
CVSS score
8.2/10
010
High · v3.1 (CVE.org)
EPSS score
0.64%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 25 · Related 22
DSA-5680-1MGASA-2024-0263MGASA-2024-0266SUSE-SU-2025:01614-1SUSE-SU-2025:01707-1SUSE-SU-2025:01919-1

Timeline

  1. 01-05-2024
    PublishedVulnerability first disclosed.
  2. 05-08-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: netfilter: br_netfilter: skip conntrack input hook for promisc packets For historical reasons, when bridge device is in promisc mode, packets that are directed to the taps follow bridge input hook path. This patch adds a workaround to reset conntrack for these packets. Jianbo Liu reports warning splats in their test infrastructure where cloned packets reach the br_netfilter input hook to confirm the conntrack object. Scratch one bit from BR_INPUT_SKB_CB to annotate that this packet has reached the input hook because it is passed up to the bridge device to reach the taps. [ 57.571874] WARNING: CPU: 1 PID: 0 at net/bridge/br_netfilter_hooks.c:616 br_nf_local_in+0x157/0x180 [br_netfilter] [ 57.572749] Modules linked in: xt_MASQUERADE nf_conntrack_netlink nfnetlink iptable_nat xt_addrtype xt_conntrack nf_nat br_netfilter rpcsec_gss_krb5 auth_rpcgss oid_registry overlay rpcrdma rdma_ucm ib_iser libiscsi scsi_transport_isc si ib_umad rdma_cm ib_ipoib iw_cm ib_cm mlx5_ib ib_uverbs ib_core mlx5ctl mlx5_core [ 57.575158] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.8.0+ #19 [ 57.575700] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 [ 57.576662] RIP: 0010:br_nf_local_in+0x157/0x180 [br_netfilter] [ 57.577195] Code: fe ff ff 41 bd 04 00 00 00 be 04 00 00 00 e9 4a ff ff ff be 04 00 00 00 48 89 ef e8 f3 a9 3c e1 66 83 ad b4 00 00 00 04 eb 91 <0f> 0b e9 f1 fe ff ff 0f 0b e9 df fe ff ff 48 89 df e8 b3 53 47 e1 [ 57.578722] RSP: 0018:ffff88885f845a08 EFLAGS: 00010202 [ 57.579207] RAX: 0000000000000002 RBX: ffff88812dfe8000 RCX: 0000000000000000 [ 57.579830] RDX: ffff88885f845a60 RSI: ffff8881022dc300 RDI: 0000000000000000 [ 57.580454] RBP: ffff88885f845a60 R08: 0000000000000001 R09: 0000000000000003 [ 57.581076] R10: 00000000ffff1300 R11: 0000000000000002 R12: 0000000000000000 [ 57.581695] R13: ffff8881047ffe00 R14: ffff888108dbee00 R15: ffff88814519b800 [ 57.582313] FS: 0000000000000000(0000) GS:ffff88885f840000(0000) knlGS:0000000000000000 [ 57.583040] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 57.583564] CR2: 000000c4206aa000 CR3: 0000000103847001 CR4: 0000000000370eb0 [ 57.584194] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 57.584820] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 57.585440] Call Trace: [ 57.585721] <IRQ> [ 57.585976] ? __warn+0x7d/0x130 [ 57.586323] ? br_nf_local_in+0x157/0x180 [br_netfilter] [ 57.586811] ? report_bug+0xf1/0x1c0 [ 57.587177] ? handle_bug+0x3f/0x70 [ 57.587539] ? exc_invalid_op+0x13/0x60 [ 57.587929] ? asm_exc_invalid_op+0x16/0x20 [ 57.588336] ? br_nf_local_in+0x157/0x180 [br_netfilter] [ 57.588825] nf_hook_slow+0x3d/0xd0 [ 57.589188] ? br_handle_vlan+0x4b/0x110 [ 57.589579] br_pass_frame_up+0xfc/0x150 [ 57.589970] ? br_port_flags_change+0x40/0x40 [ 57.590396] br_handle_frame_finish+0x346/0x5e0 [ 57.590837] ? ipt_do_table+0x32e/0x430 [ 57.591221] ? br_handle_local_finish+0x20/0x20 [ 57.591656] br_nf_hook_thresh+0x4b/0xf0 [br_netfilter] [ 57.592286] ? br_handle_local_finish+0x20/0x20 [ 57.592802] br_nf_pre_routing_finish+0x178/0x480 [br_netfilter] [ 57.593348] ? br_handle_local_finish+0x20/0x20 [ 57.593782] ? nf_nat_ipv4_pre_routing+0x25/0x60 [nf_nat] [ 57.594279] br_nf_pre_routing+0x24c/0x550 [br_netfilter] [ 57.594780] ? br_nf_hook_thresh+0xf0/0xf0 [br_netfilter] [ 57.595280] br_handle_frame+0x1f3/0x3d0 [ 57.595676] ? br_handle_local_finish+0x20/0x20 [ 57.596118] ? br_handle_frame_finish+0x5e0/0x5e0 [ 57.596566] __netif_receive_skb_core+0x25b/0xfc0 [ 57.597017] ? __napi_build_skb+0x37/0x40 [ 57.597418] __netif_receive_skb_list_core+0xfb/0x220

CVSS metrics

5 scores · 4 sources · 2 versions

EPSS trend

Probability

0.64%

Chance of exploitation in the next 30 days

Percentile

51%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.64% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Version check

Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Ubuntu102 products
  • linux< 5.15.0-116.126 | < 6.8.0-38.38
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-aws< 5.15.0-1065.71 | < 6.8.0-1011.12
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Linux2 products
  • linux≥ 7c3f28599652acf431a2211168de4a583f30b6d5, < dceb683ab87ca3666a9bb5c0158528b646faedc4 | ≥ 2b1414d5e94e477edff1d2c79030f1d742625ea0, < b13db0d16bc7b2a52abcf5cb71334f63faa5dbd6 | ≥ 80cd0487f630b5382734997c3e5e3003a77db315, < 3f59ac29dea0921637053908fe99268d157bbb9d | ≥ 62e7151ae3eb465e0ab52a20c941ff33bb6332e9, < 43193174510ea4f3ce09b796e559a2fd9f148615 | ≥ 62e7151ae3eb465e0ab52a20c941ff33bb6332e9, < 751de2012eafa4d46d8081056761fa0e9cc8a178 | cb734975b0ffa688ff6cc0eed463865bf07b6c01 | ≥ 5.15.151, < 5.15.157 | ≥ 6.1.81, < 6.1.88 | ≥ 6.6.21, < 6.6.29 | ≥ 6.7.9, < 6.8 | 6.8
  • linux_kernel≥ 5.15.151, < 5.15.157 | ≥ 6.1.81, < 6.1.88 | ≥ 6.6.21, < 6.6.29 | ≥ 6.7.9, < 6.8.8 | 6.9:rc1 | 6.9:rc2 | 6.9:rc3 | 6.9:rc4
Debian1 product
  • linux< 6.1.90-1 | < 6.8.9-1
Fedoraproject1 product

4 vendors · 106 products

References

24 links
Show all 24 references