CVE-2026-23381

MEDIUM EPSS 1.8%
Published Mar 25, 20263mo ago · Modified Jun 17, 20262w ago
5.5 CVSS 3.1
Medium
Find Similar
Published Mar 25, 2026 3mo ago
Last Modified Jun 17, 2026 2w ago

Description

In the Linux kernel, the following vulnerability has been resolved: net: bridge: fix nd_tbl NULL dereference when IPv6 is disabled When booting with the 'ipv6.disable=1' parameter, the nd_tbl is never initialized because inet6_init() exits before ndisc_init() is called which initializes it. Then, if neigh_suppress is enabled and an ICMPv6 Neighbor Discovery packet reaches the bridge, br_do_suppress_nd() will dereference ipv6_stub->nd_tbl which is NULL, passing it to neigh_lookup(). This causes a kernel NULL pointer dereference. BUG: kernel NULL pointer dereference, address: 0000000000000268 Oops: 0000 [#1] PREEMPT SMP NOPTI [...] RIP: 0010:neigh_lookup+0x16/0xe0 [...] Call Trace: <IRQ> ? neigh_lookup+0x16/0xe0 br_do_suppress_nd+0x160/0x290 [bridge] br_handle_frame_finish+0x500/0x620 [bridge] br_handle_frame+0x353/0x440 [bridge] __netif_receive_skb_core.constprop.0+0x298/0x1110 __netif_receive_skb_one_core+0x3d/0xa0 process_backlog+0xa0/0x140 __napi_poll+0x2c/0x170 net_rx_action+0x2c4/0x3a0 handle_softirqs+0xd0/0x270 do_softirq+0x3f/0x60 Fix this by replacing IS_ENABLED(IPV6) call with ipv6_mod_enabled() in the callers. This is in essence disabling NS/NA suppression when IPv6 is disabled.

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
1.8% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-476 NULL Pointer Dereference Memory Safety

Affected Products 15

VendorProductVersionRange
linuxlinux_kernel*≥4.15.1  –  <5.10.253
linuxlinux_kernel*≥5.11  –  <5.15.203
linuxlinux_kernel*≥5.16  –  <6.1.167
linuxlinux_kernel*≥6.2  –  <6.6.130
linuxlinux_kernel*≥6.7  –  <6.12.77
linuxlinux_kernel*≥6.13  –  <6.18.17
linuxlinux_kernel*≥6.19  –  <6.19.7
linuxlinux_kernel4.15any
linuxlinux_kernel7.0any
linuxlinux_kernel7.0any
linuxlinux_kernel7.0any
linuxlinux_kernel7.0any
linuxlinux_kernel7.0any
linuxlinux_kernel7.0any
linuxlinux_kernel7.0any

References 8

  • git.kernel.org https://git.kernel.org/stable/c/20ef5c25422f97dd09d751e5ae6c18406cdc78e6
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/33dec6f10777d5a8f71c0a200f690da5ae3c2e55
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/7a894eb5de246d79f13105c55a67381039a24d44
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/a12cdaa3375f0bd3c8f4e564be7c143529abfe5b
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/a5c56e65b685360dd3f2278aeff8c21061feb665
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/a9d712ccfeef737c0e700a4b5b98f310e07b6b60
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/aa73deb3b6b730ec280d45b3f423bfa9e17bc122
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/e5e890630533bdc15b26a34bb8e7ef539bdf1322
    Patch

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/20ef5c25422f97dd09d751e5ae6c18406cdc78e6
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/33dec6f10777d5a8f71c0a200f690da5ae3c2e55
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/7a894eb5de246d79f13105c55a67381039a24d44
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/a12cdaa3375f0bd3c8f4e564be7c143529abfe5b
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/a5c56e65b685360dd3f2278aeff8c21061feb665
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/a9d712ccfeef737c0e700a4b5b98f310e07b6b60
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/aa73deb3b6b730ec280d45b3f423bfa9e17bc122
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/e5e890630533bdc15b26a34bb8e7ef539bdf1322
    Patch