# CVE-2025-21708: net: usb: rtl8150: enable basic endpoint checking

> A missing endpoint type check in the Linux kernel rtl8150 USB driver allows a local attacker to trigger a kernel warning and potential denial of service.

- **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:** 27 Feb 2025
- **Updated:** 15 Oct 2026
- **Also known as:** BELL-CVE-2025-21708, DEBIAN-CVE-2025-21708, GHSA-r5rf-wpwj-h23p, ROOT-OS-UBUNTU-2404-CVE-2025-21708, UBUNTU-CVE-2025-21708

## What is CVE-2025-21708?

CVE-2025-21708 is a medium-severity denial of service vulnerability in Linux kernel, published on 27 Feb 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:

net: usb: rtl8150: enable basic endpoint checking

Syzkaller reports [1] encountering a common issue of utilizing a wrong
usb endpoint type during URB submitting stage. This, in turn, triggers
a warning shown below.

For now, enable simple endpoint checking (specifically, bulk and
interrupt eps, testing control one is not essential) to mitigate
the issue with a view to do other related cosmetic changes later,
if they are necessary.

[1] Syzkaller report:
usb 1-1: BOGUS urb xfer, pipe 3 != type 1
WARNING: CPU: 1 PID: 2586 at drivers/usb/core/urb.c:503 usb_submit_urb+0xe4b/0x1730 driv>
Modules linked in:
CPU: 1 UID: 0 PID: 2586 Comm: dhcpcd Not tainted 6.11.0-rc4-syzkaller-00069-gfc88bb11617>
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
RIP: 0010:usb_submit_urb+0xe4b/0x1730 drivers/usb/core/urb.c:503
Code: 84 3c 02 00 00 e8 05 e4 fc fc 4c 89 ef e8 fd 25 d7 fe 45 89 e0 89 e9 4c 89 f2 48 8>
RSP: 0018:ffffc9000441f740 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff888112487a00 RCX: ffffffff811a99a9
RDX: ffff88810df6ba80 RSI: ffffffff811a99b6 RDI: 0000000000000001
RBP: 0000000000000003 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001
R13: ffff8881023bf0a8 R14: ffff888112452a20 R15: ffff888112487a7c
FS:  00007fc04eea5740(0000) GS:ffff8881f6300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0a1de9f870 CR3: 000000010dbd0000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 rtl8150_open+0x300/0xe30 drivers/net/usb/rtl8150.c:733
 __dev_open+0x2d4/0x4e0 net/core/dev.c:1474
 __dev_change_flags+0x561/0x720 net/core/dev.c:8838
 dev_change_flags+0x8f/0x160 net/core/dev.c:8910
 devinet_ioctl+0x127a/0x1f10 net/ipv4/devinet.c:1177
 inet_ioctl+0x3aa/0x3f0 net/ipv4/af_inet.c:1003
 sock_do_ioctl+0x116/0x280 net/socket.c:1222
 sock_ioctl+0x22e/0x6c0 net/socket.c:1341
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl fs/ioctl.c:893 [inline]
 __x64_sys_ioctl+0x193/0x220 fs/ioctl.c:893
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc04ef73d49
...

This change has not been tested on real hardware.

## Which versions are affected by CVE-2025-21708?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2025-21708?

Apply the vendor's patch.

## Is CVE-2025-21708 being exploited?

There is no known exploitation of CVE-2025-21708 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-2025-21708 and fix it if it is affected.

What it is: CVE-2025-21708 is a medium-severity denial of service vulnerability in Linux kernel, published on 27 Feb 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-2025-21708 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-2025-21708/ (Markdown: https://insights.sbomify.com/CVE-2025-21708/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-21708
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-21708
- OSV: https://osv.dev/vulnerability/CVE-2025-21708

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-21708/
Summaries are generated and may contain mistakes; the official description above is the record.