# CVE-2023-53582: wifi: brcmfmac: ensure CLM version is null-terminated to prevent stack-out-of-bounds

> A stack-out-of-bounds read in the brcmfmac Wi-Fi driver can cause a kernel crash when processing firmware version strings.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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:** 4 Oct 2025
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2023-53582, DEBIAN-CVE-2023-53582, GHSA-958g-2hvc-2pgw, UBUNTU-CVE-2023-53582

## What is CVE-2023-53582?

CVE-2023-53582 is a medium-severity memory corruption vulnerability in Linux kernel, published on 4 Oct 2025. 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:

wifi: brcmfmac: ensure CLM version is null-terminated to prevent stack-out-of-bounds

Fix a stack-out-of-bounds read in brcmfmac that occurs
when 'buf' that is not null-terminated is passed as an argument of
strreplace() in brcmf_c_preinit_dcmds(). This buffer is filled with
a CLM version string by memcpy() in brcmf_fil_iovar_data_get().
Ensure buf is null-terminated.

Found by a modified version of syzkaller.

[   33.004414][ T1896] brcmfmac: brcmf_c_process_clm_blob: no clm_blob available (err=-2), device may have limited channels available
[   33.013486][ T1896] brcmfmac: brcmf_c_preinit_dcmds: Firmware: BCM43236/3 wl0: Nov 30 2011 17:33:42 version 5.90.188.22
[   33.021554][ T1896] ==================================================================
[   33.022379][ T1896] BUG: KASAN: stack-out-of-bounds in strreplace+0xf2/0x110
[   33.023122][ T1896] Read of size 1 at addr ffffc90001d6efc8 by task kworker/0:2/1896
[   33.023852][ T1896]
[   33.024096][ T1896] CPU: 0 PID: 1896 Comm: kworker/0:2 Tainted: G           O      5.14.0+ #132
[   33.024927][ T1896] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
[   33.026065][ T1896] Workqueue: usb_hub_wq hub_event
[   33.026581][ T1896] Call Trace:
[   33.026896][ T1896]  dump_stack_lvl+0x57/0x7d
[   33.027372][ T1896]  print_address_description.constprop.0.cold+0xf/0x334
[   33.028037][ T1896]  ? strreplace+0xf2/0x110
[   33.028403][ T1896]  ? strreplace+0xf2/0x110
[   33.028807][ T1896]  kasan_report.cold+0x83/0xdf
[   33.029283][ T1896]  ? strreplace+0xf2/0x110
[   33.029666][ T1896]  strreplace+0xf2/0x110
[   33.029966][ T1896]  brcmf_c_preinit_dcmds+0xab1/0xc40
[   33.030351][ T1896]  ? brcmf_c_set_joinpref_default+0x100/0x100
[   33.030787][ T1896]  ? rcu_read_lock_sched_held+0xa1/0xd0
[   33.031223][ T1896]  ? rcu_read_lock_bh_held+0xb0/0xb0
[   33.031661][ T1896]  ? lock_acquire+0x19d/0x4e0
[   33.032091][ T1896]  ? find_held_lock+0x2d/0x110
[   33.032605][ T1896]  ? brcmf_usb_deq+0x1a7/0x260
[   33.033087][ T1896]  ? brcmf_usb_rx_fill_all+0x5a/0xf0
[   33.033582][ T1896]  brcmf_attach+0x246/0xd40
[   33.034022][ T1896]  ? wiphy_new_nm+0x1476/0x1d50
[   33.034383][ T1896]  ? kmemdup+0x30/0x40
[   33.034722][ T1896]  brcmf_usb_probe+0x12de/0x1690
[   33.035223][ T1896]  ? brcmf_usbdev_qinit.constprop.0+0x470/0x470
[   33.035833][ T1896]  usb_probe_interface+0x25f/0x710
[   33.036315][ T1896]  really_probe+0x1be/0xa90
[   33.036656][ T1896]  __driver_probe_device+0x2ab/0x460
[   33.037026][ T1896]  ? usb_match_id.part.0+0x88/0xc0
[   33.037383][ T1896]  driver_probe_device+0x49/0x120
[   33.037790][ T1896]  __device_attach_driver+0x18a/0x250
[   33.038300][ T1896]  ? driver_allows_async_probing+0x120/0x120
[   33.038986][ T1896]  bus_for_each_drv+0x123/0x1a0
[   33.039906][ T1896]  ? bus_rescan_devices+0x20/0x20
[   33.041412][ T1896]  ? lockdep_hardirqs_on_prepare+0x273/0x3e0
[   33.041861][ T1896]  ? trace_hardirqs_on+0x1c/0x120
[   33.042330][ T1896]  __device_attach+0x207/0x330
[   33.042664][ T1896]  ? device_bind_driver+0xb0/0xb0
[   33.043026][ T1896]  ? kobject_uevent_env+0x230/0x12c0
[   33.043515][ T1896]  bus_probe_device+0x1a2/0x260
[   33.043914][ T1896]  device_add+0xa61/0x1ce0
[   33.044227][ T1896]  ? __mutex_unlock_slowpath+0xe7/0x660
[   33.044891][ T1896]  ? __fw_devlink_link_to_suppliers+0x550/0x550
[   33.045531][ T1896]  usb_set_configuration+0x984/0x1770
[   33.046051][ T1896]  ? kernfs_create_link+0x175/0x230
[   33.046548][ T1896]  usb_generic_driver_probe+0x69/0x90
[   33.046931][ T1896]  usb_probe_device+0x9c/0x220
[   33.047434][ T1896]  really_probe+0x1be/0xa90
[   33.047760][ T1896]  __driver_probe_device+0x2ab/0x460
[   33.048134][ T1896]  driver_probe_device+0x49/0x120
[   33.048516][ T1896]  __device_attach_driver+0x18a/0x250
[   33.048910][ T1896]  ? driver_allows_async_probing+0x120/0x120
---truncated---

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2023-53582?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2023-53582?

Apply the vendor's patch.

## Is CVE-2023-53582 being exploited?

There is no known exploitation of CVE-2023-53582 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-2023-53582 and fix it if it is affected.

What it is: CVE-2023-53582 is a medium-severity memory corruption vulnerability in Linux kernel, published on 4 Oct 2025. 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-2023-53582 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-2023-53582/ (Markdown: https://insights.sbomify.com/CVE-2023-53582/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-53582
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-53582
- OSV: https://osv.dev/vulnerability/CVE-2023-53582

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-53582/
Summaries are generated and may contain mistakes; the official description above is the record.
