CVE-2026-23293: Linux kernel · net: vxlan: fix nd_tbl NULL dereference when IPv6 is disabled
Affects Linux kernelSource CVE Database V5
Not known to be exploited · fixed in fbbd2118982c55fb9b0a753ae0cf7194e77149fb : update Linux kernel when convenient.
Data as of 5 Nov 2026, 22:04 UTC
Rated by Threat Radar · No CVSS score from NVD or the CNA
Thin evidence
One scorer or none- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Limited control over the software or limited information exposure
CISA SSVC assessment, 2026-11-05.
- Patch
- Available – fixed in fbbd2118982c55fb9b0a753ae0cf7194e77149fb, f0373e9317bc904e7bdb123d3106fe4f3cea2fb7, dc3e62cf3bbf66280a907ec379f373d0c3b8b2bc +5
Exploitation evidence
Disclosed: evidence found.
CVE published 25 Mar 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 5 Nov 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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Description
In the Linux kernel, the following vulnerability has been resolved: net: vxlan: 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. If an IPv6 packet is injected into the interface, route_shortcircuit() is called and a NULL pointer dereference happens on neigh_lookup(). BUG: kernel NULL pointer dereference, address: 0000000000000380 Oops: Oops: 0000 [#1] SMP NOPTI [...] RIP: 0010:neigh_lookup+0x20/0x270 [...] Call Trace: <TASK> vxlan_xmit+0x638/0x1ef0 [vxlan] dev_hard_start_xmit+0x9e/0x2e0 __dev_queue_xmit+0xbee/0x14e0 packet_sendmsg+0x116f/0x1930 __sys_sendto+0x1f5/0x200 __x64_sys_sendto+0x24/0x30 do_syscall_64+0x12f/0x1590 entry_SYSCALL_64_after_hwframe+0x76/0x7e Fix this by adding an early check on route_shortcircuit() when protocol is ETH_P_IPV6. Note that ipv6_mod_enabled() cannot be used here because VXLAN can be built-in even when IPv6 is built as a module.
References
- git.kernel.org/stable/c/649e2bb74da54c96cf20729001e283626a2fefa0 (opens in a new tab)
- git.kernel.org/stable/c/dc3e62cf3bbf66280a907ec379f373d0c3b8b2bc (opens in a new tab)
- git.kernel.org/stable/c/b5190fcd75a1f1785c766a8d1e44d3938e168f45 (opens in a new tab)
- git.kernel.org/stable/c/5f93e6b4d12bd3a4517a6d447ea675f448f21434 (opens in a new tab)
- git.kernel.org/stable/c/f0373e9317bc904e7bdb123d3106fe4f3cea2fb7 (opens in a new tab)
- git.kernel.org/stable/c/fbbd2118982c55fb9b0a753ae0cf7194e77149fb (opens in a new tab)
- git.kernel.org/stable/c/abcd48ecdeb2e12eccb8339a35534c757782afcd (opens in a new tab)
- git.kernel.org/stable/c/168ff39e4758897d2eee4756977d036d52884c7e (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-082556.html (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-019113.html (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-457936.html (opens in a new tab)