CVE-2025-38192

MEDIUM EPSS 4.4%
Published Jul 4, 202512mo ago · Modified Jun 17, 20261w ago
5.5 CVSS 3.1
Medium
Find Similar
Published Jul 4, 2025 12mo ago
Last Modified Jun 17, 2026 1w ago

Description

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 Details

Base Score
5.5
Exploitability
1.8
Impact
3.6
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High

Threat Intelligence

EPSS Exploit Probability
4.4% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-476 NULL Pointer Dereference Memory Safety

Affected Products 4

VendorProductVersionRange
linuxlinux_kernel*≥4.8  –  <6.6.95
linuxlinux_kernel*≥6.7  –  <6.12.35
linuxlinux_kernel*≥6.13  –  <6.15.4
linuxlinux_kernel6.16any

References 6

  • git.kernel.org https://git.kernel.org/stable/c/2a3ad42a57b43145839f2f233fb562247658a6d9
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/98b1d8dc9a3170b2614f1e8c93854e75cdd83980
  • git.kernel.org https://git.kernel.org/stable/c/a046f183d21ab5ace5a96ece4cf9873a42f003a7
  • git.kernel.org https://git.kernel.org/stable/c/ba9db6f907ac02215e30128770f85fbd7db2fcf9
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/bfa4d86e130a09f67607482e988313430e38f6c4
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/e9994e7b9f7bbb882d13c8191731649249150d21
    Patch

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/2a3ad42a57b43145839f2f233fb562247658a6d9
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/ba9db6f907ac02215e30128770f85fbd7db2fcf9
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/bfa4d86e130a09f67607482e988313430e38f6c4
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/e9994e7b9f7bbb882d13c8191731649249150d21
    Patch