# CVE-2023-52528: net: usb: smsc75xx: Fix uninit-value access in __smsc75xx_read_reg

> An attacker with physical access or USB privileges can trigger an uninitialized memory read in the smsc75xx driver, potentially leaking kernel memory or causing a crash.

- **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:** 2 Mar 2024
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2023-52528, DEBIAN-CVE-2023-52528, GHSA-h234-f9wp-jpmr, UBUNTU-CVE-2023-52528

## What is CVE-2023-52528?

CVE-2023-52528 is a medium-severity vulnerability in Linux kernel, published on 2 Mar 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:

net: usb: smsc75xx: Fix uninit-value access in __smsc75xx_read_reg

syzbot reported the following uninit-value access issue:

=====================================================
BUG: KMSAN: uninit-value in smsc75xx_wait_ready drivers/net/usb/smsc75xx.c:975 [inline]
BUG: KMSAN: uninit-value in smsc75xx_bind+0x5c9/0x11e0 drivers/net/usb/smsc75xx.c:1482
CPU: 0 PID: 8696 Comm: kworker/0:3 Not tainted 5.8.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: usb_hub_wq hub_event
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x21c/0x280 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 smsc75xx_wait_ready drivers/net/usb/smsc75xx.c:975 [inline]
 smsc75xx_bind+0x5c9/0x11e0 drivers/net/usb/smsc75xx.c:1482
 usbnet_probe+0x1152/0x3f90 drivers/net/usb/usbnet.c:1737
 usb_probe_interface+0xece/0x1550 drivers/usb/core/driver.c:374
 really_probe+0xf20/0x20b0 drivers/base/dd.c:529
 driver_probe_device+0x293/0x390 drivers/base/dd.c:701
 __device_attach_driver+0x63f/0x830 drivers/base/dd.c:807
 bus_for_each_drv+0x2ca/0x3f0 drivers/base/bus.c:431
 __device_attach+0x4e2/0x7f0 drivers/base/dd.c:873
 device_initial_probe+0x4a/0x60 drivers/base/dd.c:920
 bus_probe_device+0x177/0x3d0 drivers/base/bus.c:491
 device_add+0x3b0e/0x40d0 drivers/base/core.c:2680
 usb_set_configuration+0x380f/0x3f10 drivers/usb/core/message.c:2032
 usb_generic_driver_probe+0x138/0x300 drivers/usb/core/generic.c:241
 usb_probe_device+0x311/0x490 drivers/usb/core/driver.c:272
 really_probe+0xf20/0x20b0 drivers/base/dd.c:529
 driver_probe_device+0x293/0x390 drivers/base/dd.c:701
 __device_attach_driver+0x63f/0x830 drivers/base/dd.c:807
 bus_for_each_drv+0x2ca/0x3f0 drivers/base/bus.c:431
 __device_attach+0x4e2/0x7f0 drivers/base/dd.c:873
 device_initial_probe+0x4a/0x60 drivers/base/dd.c:920
 bus_probe_device+0x177/0x3d0 drivers/base/bus.c:491
 device_add+0x3b0e/0x40d0 drivers/base/core.c:2680
 usb_new_device+0x1bd4/0x2a30 drivers/usb/core/hub.c:2554
 hub_port_connect drivers/usb/core/hub.c:5208 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5348 [inline]
 port_event drivers/usb/core/hub.c:5494 [inline]
 hub_event+0x5e7b/0x8a70 drivers/usb/core/hub.c:5576
 process_one_work+0x1688/0x2140 kernel/workqueue.c:2269
 worker_thread+0x10bc/0x2730 kernel/workqueue.c:2415
 kthread+0x551/0x590 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293

Local variable ----buf.i87@smsc75xx_bind created at:
 __smsc75xx_read_reg drivers/net/usb/smsc75xx.c:83 [inline]
 smsc75xx_wait_ready drivers/net/usb/smsc75xx.c:968 [inline]
 smsc75xx_bind+0x485/0x11e0 drivers/net/usb/smsc75xx.c:1482
 __smsc75xx_read_reg drivers/net/usb/smsc75xx.c:83 [inline]
 smsc75xx_wait_ready drivers/net/usb/smsc75xx.c:968 [inline]
 smsc75xx_bind+0x485/0x11e0 drivers/net/usb/smsc75xx.c:1482

This issue is caused because usbnet_read_cmd() reads less bytes than requested
(zero byte in the reproducer). In this case, 'buf' is not properly filled.

This patch fixes the issue by returning -ENODATA if usbnet_read_cmd() reads
less bytes than requested.

Weakness: CWE-908 (Use of Uninitialized Resource)

## Which versions are affected by CVE-2023-52528?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2023-52528?

Apply the vendor's patch.

## Is CVE-2023-52528 being exploited?

There is no known exploitation of CVE-2023-52528 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-2023-52528 and fix it if it is affected.

What it is: CVE-2023-52528 is a medium-severity vulnerability in Linux kernel, published on 2 Mar 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-2023-52528 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-2023-52528/ (Markdown: https://insights.sbomify.com/CVE-2023-52528/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-52528
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-52528
- OSV: https://osv.dev/vulnerability/CVE-2023-52528

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-52528/
Summaries are generated and may contain mistakes; the official description above is the record.
