CVE-2024-50045netfilter: br_netfilter: fix panic with metadata_dst skb
Updated under an hour ago ()
Does this affect you?
It affects Linux and 8 other products. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
Do this next
Free account, 1 product
In the Linux kernel, the following vulnerability has been resolved: netfilter: br_netfilter: fix panic with metadata_dst skb Fix a kernel panic in the br_netfilter module when sending untagged traffic via a VxLAN device. This happens during the check for fragmentation in br_nf_dev_queue_xmit. It is dependent on: 1) the br_netfilter module being loaded; 2) net.bridge.bridge-nf-call-iptables set to 1; 3) a bridge with a VxLAN (single-vxlan-device) netdevice as a bridge port; 4) untagged frames with size higher than the VxLAN MTU forwarded/flooded When forwarding the untagged packet to the VxLAN bridge port, before the netfilter hooks are called, br_handle_egress_vlan_tunnel is called and changes the skb_dst to the tunnel dst. The tunnel_dst is a metadata type of dst, i.e., skb_valid_dst(skb) is false, and metadata->dst.dev is NULL. Then in the br_netfilter hooks, in br_nf_dev_queue_xmit, there's a check for frames that needs to be fragmented: frames with higher MTU than the VxLAN device end up calling br_nf_ip_fragment, which in turns call ip_skb_dst_mtu. The ip_dst_mtu tries to use the skb_dst(skb) as if it was a valid dst with valid dst->dev, thus the crash. This case was never supported in the first place, so drop the packet instead. PING 10.0.0.2 (10.0.0.2) from 0.0.0.0 h1-eth0: 2000(2028) bytes of data. [ 176.291791] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000110 [ 176.292101] Mem abort info: [ 176.292184] ESR = 0x0000000096000004 [ 176.292322] EC = 0x25: DABT (current EL), IL = 32 bits [ 176.292530] SET = 0, FnV = 0 [ 176.292709] EA = 0, S1PTW = 0 [ 176.292862] FSC = 0x04: level 0 translation fault [ 176.293013] Data abort info: [ 176.293104] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 [ 176.293488] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 176.293787] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 176.293995] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000043ef5000 [ 176.294166] [0000000000000110] pgd=0000000000000000, p4d=0000000000000000 [ 176.294827] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP [ 176.295252] Modules linked in: vxlan ip6_udp_tunnel udp_tunnel veth br_netfilter bridge stp llc ipv6 crct10dif_ce [ 176.295923] CPU: 0 PID: 188 Comm: ping Not tainted 6.8.0-rc3-g5b3fbd61b9d1 #2 [ 176.296314] Hardware name: linux,dummy-virt (DT) [ 176.296535] pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 176.296808] pc : br_nf_dev_queue_xmit+0x390/0x4ec [br_netfilter] [ 176.297382] lr : br_nf_dev_queue_xmit+0x2ac/0x4ec [br_netfilter] [ 176.297636] sp : ffff800080003630 [ 176.297743] x29: ffff800080003630 x28: 0000000000000008 x27: ffff6828c49ad9f8 [ 176.298093] x26: ffff6828c49ad000 x25: 0000000000000000 x24: 00000000000003e8 [ 176.298430] x23: 0000000000000000 x22: ffff6828c4960b40 x21: ffff6828c3b16d28 [ 176.298652] x20: ffff6828c3167048 x19: ffff6828c3b16d00 x18: 0000000000000014 [ 176.298926] x17: ffffb0476322f000 x16: ffffb7e164023730 x15: 0000000095744632 [ 176.299296] x14: ffff6828c3f1c880 x13: 0000000000000002 x12: ffffb7e137926a70 [ 176.299574] x11: 0000000000000001 x10: ffff6828c3f1c898 x9 : 0000000000000000 [ 176.300049] x8 : ffff6828c49bf070 x7 : 0008460f18d5f20e x6 : f20e0100bebafeca [ 176.300302] x5 : ffff6828c7f918fe x4 : ffff6828c49bf070 x3 : 0000000000000000 [ 176.300586] x2 : 0000000000000000 x1 : ffff6828c3c7ad00 x0 : ffff6828c7f918f0 [ 176.300889] Call trace: [ 176.301123] br_nf_dev_queue_xmit+0x390/0x4ec [br_netfilter] [ 176.301411] br_nf_post_routing+0x2a8/0x3e4 [br_netfilter] [ 176.301703] nf_hook_slow+0x48/0x124 [ 176.302060] br_forward_finish+0xc8/0xe8 [bridge] [ 176.302371] br_nf_hook_thresh+0x124/0x134 [br_netfilter] [ 176.302605] br_nf_forward_finish+0x118/0x22c [br_netfilter] [ 176.302824] br_nf_forward_ip.part.0+0x264/0x290 [br_netfilter] [ 176.303136] br_nf_forward+0x2b8/0x4e0 [br_netfilter] [ 176.303359] nf_hook_slow+0x48/0x124 [ 176.303 ---truncated---
- CVSS
- 7.5 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Weakness (CWE)
- Not given
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- Linux
- NVD analysis
- Modified
- Record last updated
- Oct 15, 2026
- First seen by InfoSec Signals
- Oct 15, 2026
Affected products
Linux Linux linux:linux (from the name) | from 11538d039ac6efcf4f1a6c536e1b87cd3668a9fd before f07131239a76cc10d5e82c19d91f53cb55727297; 11538d039ac6efcf4f1a6c536e1b87cd3668a9fd builds before 75dfcb758015c97e1accd6340691fca67d363bed; from 11538d039ac6efcf4f1a6c536e1b87cd3668a9fd before cce8419b8168f6e7eb637103a47f916f3de8bc81; 11538d039ac6efcf4f1a6c536e1b87cd3668a9fd builds before 95c0cff5a1a5d28bf623b92eb5d1a8f56ed30803; 11538d039ac6efcf4f1a6c536e1b87cd3668a9fd builds before 78ed917133b118661e1fe62d4a85d5d428ee9568; 11538d039ac6efcf4f1a6c536e1b87cd3668a9fd builds before 3453f5839420bfbb85c86c61e49f49ffd0f041c4; from 11538d039ac6efcf4f1a6c536e1b87cd3668a9fd before 915717e0bb9837cc5c101bc545af487bd787239e; from 11538d039ac6efcf4f1a6c536e1b87cd3668a9fd before f9ff7665cd128012868098bbd07e28993e314fdb | CNA record |
Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP siemens:simatic_s7_1500_cpu_1518_4_pn_dp_mfp (from the name) | from V3.1.0 before V3.1.5 | CISA ADP |
Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP siemens:simatic_s7_1500_cpu_1518f_4_pn_dp_mfp (from the name) | from V3.1.0 before V3.1.5 | CISA ADP |
Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem siemens:simatic_s7_1500_tm_mfp_gnu_linux_subsystem (from the name) | before V1.1.1 | CISA ADP |
Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP siemens:siplus_s7_1500_cpu_1518_4_pn_dp_mfp (from the name) | from V3.1.0 before V3.1.5 | CISA ADP |
Siemens RUGGEDCOM RST2428P siemens:ruggedcom_rst2428p (from the name) | before V3.2 | CISA ADP |
Siemens SCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500 family siemens:scalance_xc_300_xr_300_xc_400_xr_500wg_xr_500_family (from the name) | before V3.2 | CISA ADP |
Siemens SCALANCE XCM-/XRM-/XCH-/XRH-300 family siemens:scalance_xcm_xrm_xch_xrh_300_family (from the name) | before V3.2 | CISA ADP |
linux linux_kernel linux:linux_kernel | from 4.11 before 5.10.227; from 5.11 before 5.15.168; from 5.16 before 6.1.113; from 6.2 before 6.6.57; from 6.7 before 6.11.4; 6.12; 6.12 | NVD |
References
- https://git.kernel.org/stable/c/f07131239a76cc10d5e82c19d91f53cb55727297
- https://git.kernel.org/stable/c/75dfcb758015c97e1accd6340691fca67d363bed
- https://git.kernel.org/stable/c/cce8419b8168f6e7eb637103a47f916f3de8bc81patch
- https://git.kernel.org/stable/c/95c0cff5a1a5d28bf623b92eb5d1a8f56ed30803patch
- https://git.kernel.org/stable/c/78ed917133b118661e1fe62d4a85d5d428ee9568patch
- https://git.kernel.org/stable/c/3453f5839420bfbb85c86c61e49f49ffd0f041c4patch
- https://git.kernel.org/stable/c/915717e0bb9837cc5c101bc545af487bd787239epatch
- https://git.kernel.org/stable/c/f9ff7665cd128012868098bbd07e28993e314fdbpatch
- https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html
- https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html
- https://cert-portal.siemens.com/productcert/html/ssa-265688.html
- https://cert-portal.siemens.com/productcert/html/ssa-355557.html
- https://cert-portal.siemens.com/productcert/html/ssa-398330.html
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.