# CVE-2024-26961: mac802154: fix llsec key resources release in mac802154_llsec_key_del

> A use-after-free vulnerability in the Linux kernel's mac802154 module allows attackers to potentially execute code or escalate privileges via race conditions during key deletion.

- **Severity:** High 7.0 (`CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 1 May 2024
- **Updated:** 15 Oct 2026
- **Also known as:** AZL-40481, BELL-CVE-2024-26961, DEBIAN-CVE-2024-26961, GHSA-7533-c28p-jp9p, UBUNTU-CVE-2024-26961

## What is CVE-2024-26961?

CVE-2024-26961 is a high-severity use after free vulnerability in Linux kernel, published on 1 May 2024. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

mac802154: fix llsec key resources release in mac802154_llsec_key_del

mac802154_llsec_key_del() can free resources of a key directly without
following the RCU rules for waiting before the end of a grace period. This
may lead to use-after-free in case llsec_lookup_key() is traversing the
list of keys in parallel with a key deletion:

refcount_t: addition on 0; use-after-free.
WARNING: CPU: 4 PID: 16000 at lib/refcount.c:25 refcount_warn_saturate+0x162/0x2a0
Modules linked in:
CPU: 4 PID: 16000 Comm: wpan-ping Not tainted 6.7.0 #19
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:refcount_warn_saturate+0x162/0x2a0
Call Trace:
 <TASK>
 llsec_lookup_key.isra.0+0x890/0x9e0
 mac802154_llsec_encrypt+0x30c/0x9c0
 ieee802154_subif_start_xmit+0x24/0x1e0
 dev_hard_start_xmit+0x13e/0x690
 sch_direct_xmit+0x2ae/0xbc0
 __dev_queue_xmit+0x11dd/0x3c20
 dgram_sendmsg+0x90b/0xd60
 __sys_sendto+0x466/0x4c0
 __x64_sys_sendto+0xe0/0x1c0
 do_syscall_64+0x45/0xf0
 entry_SYSCALL_64_after_hwframe+0x6e/0x76

Also, ieee802154_llsec_key_entry structures are not freed by
mac802154_llsec_key_del():

unreferenced object 0xffff8880613b6980 (size 64):
  comm "iwpan", pid 2176, jiffies 4294761134 (age 60.475s)
  hex dump (first 32 bytes):
    78 0d 8f 18 80 88 ff ff 22 01 00 00 00 00 ad de  x.......".......
    00 00 00 00 00 00 00 00 03 00 cd ab 00 00 00 00  ................
  backtrace:
    [<ffffffff81dcfa62>] __kmem_cache_alloc_node+0x1e2/0x2d0
    [<ffffffff81c43865>] kmalloc_trace+0x25/0xc0
    [<ffffffff88968b09>] mac802154_llsec_key_add+0xac9/0xcf0
    [<ffffffff8896e41a>] ieee802154_add_llsec_key+0x5a/0x80
    [<ffffffff8892adc6>] nl802154_add_llsec_key+0x426/0x5b0
    [<ffffffff86ff293e>] genl_family_rcv_msg_doit+0x1fe/0x2f0
    [<ffffffff86ff46d1>] genl_rcv_msg+0x531/0x7d0
    [<ffffffff86fee7a9>] netlink_rcv_skb+0x169/0x440
    [<ffffffff86ff1d88>] genl_rcv+0x28/0x40
    [<ffffffff86fec15c>] netlink_unicast+0x53c/0x820
    [<ffffffff86fecd8b>] netlink_sendmsg+0x93b/0xe60
    [<ffffffff86b91b35>] ____sys_sendmsg+0xac5/0xca0
    [<ffffffff86b9c3dd>] ___sys_sendmsg+0x11d/0x1c0
    [<ffffffff86b9c65a>] __sys_sendmsg+0xfa/0x1d0
    [<ffffffff88eadbf5>] do_syscall_64+0x45/0xf0
    [<ffffffff890000ea>] entry_SYSCALL_64_after_hwframe+0x6e/0x76

Handle the proper resource release in the RCU callback function
mac802154_llsec_key_del_rcu().

Note that if llsec_lookup_key() finds a key, it gets a refcount via
llsec_key_get() and locally copies key id from key_entry (which is a
list element). So it's safe to call llsec_key_put() and free the list
entry after the RCU grace period elapses.

Found by Linux Verification Center (linuxtesting.org).

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2024-26961?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-26961?

Apply the vendor's patch.

## Is CVE-2024-26961 being exploited?

There is no known exploitation of CVE-2024-26961 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-26961 and fix it if it is affected.

What it is: CVE-2024-26961 is a high-severity use after free vulnerability in Linux kernel, published on 1 May 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2024-26961 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2024-26961/ (Markdown: https://insights.sbomify.com/CVE-2024-26961/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-26961
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-26961
- OSV: https://osv.dev/vulnerability/CVE-2024-26961

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-26961/
Summaries are generated and may contain mistakes; the official description above is the record.
