# CVE-2023-53679: wifi: mt7601u: fix an integer underflow

> An attacker can cause a kernel crash via integer underflow in the mt7601u WiFi driver, leading to a null pointer dereference.

- **Severity:** High 8.3 (`CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 7 Oct 2025
- **Updated:** 15 Oct 2026
- **Also known as:** BELL-CVE-2023-53679, DEBIAN-CVE-2023-53679, GHSA-w427-vv2j-48v6, UBUNTU-CVE-2023-53679

## What is CVE-2023-53679?

CVE-2023-53679 is a high-severity vulnerability in Linux kernel, published on 7 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: mt7601u: fix an integer underflow

Fix an integer underflow that leads to a null pointer dereference in
'mt7601u_rx_skb_from_seg()'. The variable 'dma_len' in the URB packet
could be manipulated, which could trigger an integer underflow of
'seg_len' in 'mt7601u_rx_process_seg()'. This underflow subsequently
causes the 'bad_frame' checks in 'mt7601u_rx_skb_from_seg()' to be
bypassed, eventually leading to a dereference of the pointer 'p', which
is a null pointer.

Ensure that 'dma_len' is greater than 'min_seg_len'.

Found by a modified version of syzkaller.

KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 0 PID: 12 Comm: ksoftirqd/0 Tainted: G        W  O      5.14.0+
#139
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
RIP: 0010:skb_add_rx_frag+0x143/0x370
Code: e2 07 83 c2 03 38 ca 7c 08 84 c9 0f 85 86 01 00 00 4c 8d 7d 08 44
89 68 08 48 b8 00 00 00 00 00 fc ff df 4c 89 fa 48 c1 ea 03 <80> 3c 02
00 0f 85 cd 01 00 00 48 8b 45 08 a8 01 0f 85 3d 01 00 00
RSP: 0018:ffffc900000cfc90 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff888115520dc0 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffff8881118430c0 RDI: ffff8881118430f8
RBP: 0000000000000000 R08: 0000000000000e09 R09: 0000000000000010
R10: ffff888111843017 R11: ffffed1022308602 R12: 0000000000000000
R13: 0000000000000e09 R14: 0000000000000010 R15: 0000000000000008
FS:  0000000000000000(0000) GS:ffff88811a800000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000004035af40 CR3: 00000001157f2000 CR4: 0000000000750ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
 mt7601u_rx_tasklet+0xc73/0x1270
 ? mt7601u_submit_rx_buf.isra.0+0x510/0x510
 ? tasklet_action_common.isra.0+0x79/0x2f0
 tasklet_action_common.isra.0+0x206/0x2f0
 __do_softirq+0x1b5/0x880
 ? tasklet_unlock+0x30/0x30
 run_ksoftirqd+0x26/0x50
 smpboot_thread_fn+0x34f/0x7d0
 ? smpboot_register_percpu_thread+0x370/0x370
 kthread+0x3a1/0x480
 ? set_kthread_struct+0x120/0x120
 ret_from_fork+0x1f/0x30
Modules linked in: 88XXau(O) 88x2bu(O)
---[ end trace 57f34f93b4da0f9b ]---
RIP: 0010:skb_add_rx_frag+0x143/0x370
Code: e2 07 83 c2 03 38 ca 7c 08 84 c9 0f 85 86 01 00 00 4c 8d 7d 08 44
89 68 08 48 b8 00 00 00 00 00 fc ff df 4c 89 fa 48 c1 ea 03 <80> 3c 02
00 0f 85 cd 01 00 00 48 8b 45 08 a8 01 0f 85 3d 01 00 00
RSP: 0018:ffffc900000cfc90 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff888115520dc0 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffff8881118430c0 RDI: ffff8881118430f8
RBP: 0000000000000000 R08: 0000000000000e09 R09: 0000000000000010
R10: ffff888111843017 R11: ffffed1022308602 R12: 0000000000000000
R13: 0000000000000e09 R14: 0000000000000010 R15: 0000000000000008
FS:  0000000000000000(0000) GS:ffff88811a800000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000004035af40 CR3: 00000001157f2000 CR4: 0000000000750ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554

Weakness: CWE-191 (Integer Underflow (Wrap or Wraparound))

## Which versions are affected by CVE-2023-53679?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2023-53679?

Apply the vendor's patch.

## Is CVE-2023-53679 being exploited?

There is no known exploitation of CVE-2023-53679 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-2023-53679 and fix it if it is affected.

What it is: CVE-2023-53679 is a high-severity vulnerability in Linux kernel, published on 7 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-2023-53679 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-2023-53679/ (Markdown: https://insights.sbomify.com/CVE-2023-53679/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-53679
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-53679
- OSV: https://osv.dev/vulnerability/CVE-2023-53679

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-53679/
Summaries are generated and may contain mistakes; the official description above is the record.