CVE-2026-23279
What it is
In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: fix NULL pointer dereference in mesh_rx_csa_frame() In mesh_rx_csa_frame(), elems->mesh_chansw_params_ie is dereferenced at lines 1638 and 1642 without a prior NULL check: ifmsh->chsw_ttl = elems->mesh_chansw_params_ie->mesh_ttl; ... pre_value = le16_to_cpu(elems->mesh_chansw_params_ie->mesh_pre_value); The mesh_matches_local() check above only validates the Mesh ID, Mesh Configuration, and Supported Rates IEs. It does not verify the presence of the Mesh Channel Switch Parameters IE (element ID 118). When a received CSA action frame omits that IE, ieee802_11_parse_elems() leaves elems->mesh_chansw_params_ie as NULL, and the unconditional dereference causes a kernel NULL pointer dereference. A remote mesh peer with an established peer link (PLINK_ESTAB) can trigger this by sending a crafted SPECTRUM_MGMT/CHL_SWITCH action frame that includes a matching Mesh ID and Mesh Configuration IE but omits the Mesh Channel Switch Parameters IE. No authentication beyond the default open mesh peering is required. Crash confirmed on kernel 6.17.0-5-generic via mac80211_hwsim: BUG: kernel NULL pointer dereference, address: 0000000000000000 Oops: Oops: 0000 [#1] SMP NOPTI RIP: 0010:ieee80211_mesh_rx_queued_mgmt+0x143/0x2a0 [mac80211] CR2: 0000000000000000 Fix by adding a NULL check for mesh_chansw_params_ie after mesh_matches_local() returns, consistent with how other optional IEs are guarded throughout the mesh code. The bug has been present since v3.13 (released 2014-01-19).
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 < 6.12.77
- Linux Kernel < 6.18.17
- Linux Kernel < 6.19.7
- Linux Kernel 7.0
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-2026-23279.md and follow it. Check whether this project is affected by CVE-2026-23279. 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/017c1792525064a723971f0216e6ef86a8c7af11
- https://git.kernel.org/stable/c/22a9adea7e26d236406edc0ea00b54351dd56b9c
- https://git.kernel.org/stable/c/2b5f282b1b7241ef624c3399a1cdff0bb1a3eeab
- https://git.kernel.org/stable/c/753ad20dcbe36b67088c7770d8fc357d7cc43e08
- https://git.kernel.org/stable/c/be8b82c567fda86f2cbb43b7208825125bb31421
- https://git.kernel.org/stable/c/cc6d5a3c0a854aeae00915fc5386570c86029c60
- https://git.kernel.org/stable/c/f061336f072ab03fd29270ae61fede46bf8fd69d
- https://git.kernel.org/stable/c/f5d8af683410a8c82e48b51291915bd612523d9a
References
- https://git.kernel.org/stable/c/017c1792525064a723971f0216e6ef86a8c7af11
- https://git.kernel.org/stable/c/22a9adea7e26d236406edc0ea00b54351dd56b9c
- https://git.kernel.org/stable/c/2b5f282b1b7241ef624c3399a1cdff0bb1a3eeab
- https://git.kernel.org/stable/c/753ad20dcbe36b67088c7770d8fc357d7cc43e08
- https://git.kernel.org/stable/c/be8b82c567fda86f2cbb43b7208825125bb31421
- https://git.kernel.org/stable/c/cc6d5a3c0a854aeae00915fc5386570c86029c60
- https://git.kernel.org/stable/c/f061336f072ab03fd29270ae61fede46bf8fd69d
- https://git.kernel.org/stable/c/f5d8af683410a8c82e48b51291915bd612523d9a
- https://cert-portal.siemens.com/productcert/html/ssa-784472.html