CVE-2026-23396
What it is
In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: fix NULL deref in mesh_matches_local() mesh_matches_local() unconditionally dereferences ie->mesh_config to compare mesh configuration parameters. When called from mesh_rx_csa_frame(), the parsed action-frame elements may not contain a Mesh Configuration IE, leaving ie->mesh_config NULL and triggering a kernel NULL pointer dereference. The other two callers are already safe: - ieee80211_mesh_rx_bcn_presp() checks !elems->mesh_config before calling mesh_matches_local() - mesh_plink_get_event() is only reached through mesh_process_plink_frame(), which checks !elems->mesh_config, too mesh_rx_csa_frame() is the only caller that passes raw parsed elements to mesh_matches_local() without guarding mesh_config. An adjacent attacker can exploit this by sending a crafted CSA action frame that includes a valid Mesh ID IE but omits the Mesh Configuration IE, crashing the kernel. The captured crash log: Oops: general protection fault, probably for non-canonical address ... KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] Workqueue: events_unbound cfg80211_wiphy_work [...] Call Trace: <TASK> ? __pfx_mesh_matches_local (net/mac80211/mesh.c:65) ieee80211_mesh_rx_queued_mgmt (net/mac80211/mesh.c:1686) [...] ieee80211_iface_work (net/mac80211/iface.c:1754 net/mac80211/iface.c:1802) [...] cfg80211_wiphy_work (net/wireless/core.c:426) process_one_work (net/kernel/workqueue.c:3280) ? assign_work (net/kernel/workqueue.c:1219) worker_thread (net/kernel/workqueue.c:3352) ? __pfx_worker_thread (net/kernel/workqueue.c:3385) kthread (net/kernel/kthread.c:436) [...] ret_from_fork_asm (net/arch/x86/entry/entry_64.S:255) </TASK> This patch adds a NULL check for ie->mesh_config at the top of mesh_matches_local() to return false early when the Mesh Configuration IE is absent.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of service disruption.
- Exploit odds
- 0.1% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.1% in the next 30 days (EPSS).
- Severity: 5.5 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.1% · EPSS, next 30 days
- Weakness
- CWE-476 · NULL pointer dereference
- Record status
- Modified
Affected
- Linux Kernel < 5.10.253
- Linux Kernel < 5.15.203
- Linux Kernel < 6.1.167
- Linux Kernel < 6.6.130
- Linux Kernel < 6.12.78
- Linux Kernel < 6.18.20
- Linux Kernel < 6.19.10
- Linux Kernel 2.6.26
Attack profile CVSS 3.1 · 5.5
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-23396.md and follow it. Check whether this project is affected by CVE-2026-23396. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/0a4da176ae4b4e075a19c00d3e269cfd5e05a813
- https://git.kernel.org/stable/c/14a4fd13657a3f2489db6566f081adfb27a49c64
- https://git.kernel.org/stable/c/44699c6cdfce80a0f296b54ae9314461e3e41b3d
- https://git.kernel.org/stable/c/74de6fa472b03bc8cde0a081484e9960bcbda568
- https://git.kernel.org/stable/c/7c55a3deaf7eaaafa2546f8de7fed19382a0a116
- https://git.kernel.org/stable/c/a90279e7f7ea0b7e923a1c5ebee9a6b78b6d1004
- https://git.kernel.org/stable/c/c1e3f2416fb27c816ce96d747d3e784e31f4d95c
- https://git.kernel.org/stable/c/c73bb9a2d33bf81f6eecaa0f474b6c6dbe9855bd
References
- https://git.kernel.org/stable/c/0a4da176ae4b4e075a19c00d3e269cfd5e05a813
- https://git.kernel.org/stable/c/14a4fd13657a3f2489db6566f081adfb27a49c64
- https://git.kernel.org/stable/c/44699c6cdfce80a0f296b54ae9314461e3e41b3d
- https://git.kernel.org/stable/c/74de6fa472b03bc8cde0a081484e9960bcbda568
- https://git.kernel.org/stable/c/7c55a3deaf7eaaafa2546f8de7fed19382a0a116
- https://git.kernel.org/stable/c/a90279e7f7ea0b7e923a1c5ebee9a6b78b6d1004
- https://git.kernel.org/stable/c/c1e3f2416fb27c816ce96d747d3e784e31f4d95c
- https://git.kernel.org/stable/c/c73bb9a2d33bf81f6eecaa0f474b6c6dbe9855bd
- https://cert-portal.siemens.com/productcert/html/ssa-784472.html