CVE-2025-38192net: clear the dst when changing skb protocol
Updated under an hour ago ()
Does this affect you?
It affects Linux and 5 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: net: clear the dst when changing skb protocol A not-so-careful NAT46 BPF program can crash the kernel if it indiscriminately flips ingress packets from v4 to v6: BUG: kernel NULL pointer dereference, address: 0000000000000000 ip6_rcv_core (net/ipv6/ip6_input.c:190:20) ipv6_rcv (net/ipv6/ip6_input.c:306:8) process_backlog (net/core/dev.c:6186:4) napi_poll (net/core/dev.c:6906:9) net_rx_action (net/core/dev.c:7028:13) do_softirq (kernel/softirq.c:462:3) netif_rx (net/core/dev.c:5326:3) dev_loopback_xmit (net/core/dev.c:4015:2) ip_mc_finish_output (net/ipv4/ip_output.c:363:8) NF_HOOK (./include/linux/netfilter.h:314:9) ip_mc_output (net/ipv4/ip_output.c:400:5) dst_output (./include/net/dst.h:459:9) ip_local_out (net/ipv4/ip_output.c:130:9) ip_send_skb (net/ipv4/ip_output.c:1496:8) udp_send_skb (net/ipv4/udp.c:1040:8) udp_sendmsg (net/ipv4/udp.c:1328:10) The output interface has a 4->6 program attached at ingress. We try to loop the multicast skb back to the sending socket. Ingress BPF runs as part of netif_rx(), pushes a valid v6 hdr and changes skb->protocol to v6. We enter ip6_rcv_core which tries to use skb_dst(). But the dst is still an IPv4 one left after IPv4 mcast output. Clear the dst in all BPF helpers which change the protocol. Try to preserve metadata dsts, those may carry non-routing metadata.
- CVSS
- 7.8 HIGH (v3.1, CNA)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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 6578171a7ff0c31dc73258f93da7407510abf085 before a046f183d21ab5ace5a96ece4cf9873a42f003a7; 6578171a7ff0c31dc73258f93da7407510abf085 builds before 98b1d8dc9a3170b2614f1e8c93854e75cdd83980; from 6578171a7ff0c31dc73258f93da7407510abf085 before bfa4d86e130a09f67607482e988313430e38f6c4; 6578171a7ff0c31dc73258f93da7407510abf085 builds before 2a3ad42a57b43145839f2f233fb562247658a6d9; from 6578171a7ff0c31dc73258f93da7407510abf085 before e9994e7b9f7bbb882d13c8191731649249150d21; from 6578171a7ff0c31dc73258f93da7407510abf085 before ba9db6f907ac02215e30128770f85fbd7db2fcf9 | 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 V3.1.6 | 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 V3.1.6 | CISA ADP |
Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem siemens:simatic_s7_1500_tm_mfp_gnu_linux_subsystem (from the name) | all versions | 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 V3.1.6 | CISA ADP |
linux linux_kernel linux:linux_kernel | from 4.8 before 6.6.95; from 6.7 before 6.12.35; from 6.13 before 6.15.4; 6.16 | NVD |
References
- https://git.kernel.org/stable/c/a046f183d21ab5ace5a96ece4cf9873a42f003a7
- https://git.kernel.org/stable/c/98b1d8dc9a3170b2614f1e8c93854e75cdd83980
- https://git.kernel.org/stable/c/bfa4d86e130a09f67607482e988313430e38f6c4patch
- https://git.kernel.org/stable/c/2a3ad42a57b43145839f2f233fb562247658a6d9patch
- https://git.kernel.org/stable/c/e9994e7b9f7bbb882d13c8191731649249150d21patch
- https://git.kernel.org/stable/c/ba9db6f907ac02215e30128770f85fbd7db2fcf9patch
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html
- https://cert-portal.siemens.com/productcert/html/ssa-082556.html
- https://cert-portal.siemens.com/productcert/html/ssa-457936.html
- https://cert-portal.siemens.com/productcert/html/ssa-784472.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.