CVE-2026-23293: net: vxlan: fix nd_tbl NULL dereference when IPv6 is disabled
Vulnerability summary
CVE-2026-23293 is a medium (CVSS 5.5) NULL Pointer Dereference vulnerability in linux. EPSS estimates a 0.13% chance of exploitation in the next 30 days, higher than 2.9% of scored vulnerabilities.
Not severe (CVSS 5.5, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 38 · Related 36Timeline
- 25-03-2026PublishedVulnerability first disclosed.
- 15-10-2026Last modifiedVulnerability information updated.
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.
CVSS metrics
3 scores · 3 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.13%
Chance of exploitation in the next 30 days
Percentile
3%
Versus all other CVEs
30-day change
Increase +0.01 pp
From 0.13% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu157 products
- linuxAll versions (No fix recorded) | < 5.15.0-186.196 | < 6.8.0-136.136
- linux-allwinner-5.19All versions (No fix recorded)
- linux-awsAll versions (No fix recorded) | < 5.15.0-1112.119 | < 6.8.0-1061.64
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Linux2 products
- linux≥ e15a00aafa4b7953ad717d3cb1ad7acf4ff76945, < 649e2bb74da54c96cf20729001e283626a2fefa0 | ≥ e15a00aafa4b7953ad717d3cb1ad7acf4ff76945, < dc3e62cf3bbf66280a907ec379f373d0c3b8b2bc | ≥ e15a00aafa4b7953ad717d3cb1ad7acf4ff76945, < b5190fcd75a1f1785c766a8d1e44d3938e168f45 | ≥ e15a00aafa4b7953ad717d3cb1ad7acf4ff76945, < 5f93e6b4d12bd3a4517a6d447ea675f448f21434 | ≥ e15a00aafa4b7953ad717d3cb1ad7acf4ff76945, < f0373e9317bc904e7bdb123d3106fe4f3cea2fb7 | ≥ e15a00aafa4b7953ad717d3cb1ad7acf4ff76945, < fbbd2118982c55fb9b0a753ae0cf7194e77149fb | ≥ e15a00aafa4b7953ad717d3cb1ad7acf4ff76945, < abcd48ecdeb2e12eccb8339a35534c757782afcd | ≥ e15a00aafa4b7953ad717d3cb1ad7acf4ff76945, < 168ff39e4758897d2eee4756977d036d52884c7e | 3.12
- linux_kernel≥ 3.12, < 5.10.253 | ≥ 5.11, < 5.15.203 | ≥ 5.16, < 6.1.167 | ≥ 6.2, < 6.6.130 | ≥ 6.7, < 6.12.77 | ≥ 6.13, < 6.18.17 | ≥ 6.19, < 6.19.7 | 7.0:rc1 | 7.0:rc2
Debian1 product
- linux< 6.1.170-1 | < 6.12.85-1 | < 6.19.8-1
3 vendors · 160 products
