# CVE-2023-54186: usb: typec: altmodes/displayport: fix pin_assignment_show

> A use-after-free vulnerability in the Linux kernel's USB Type-C DisplayPort driver allows local attackers to cause a system crash via negative array indexing.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/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:** 30 Dec 2025
- **Updated:** 5 Aug 2026
- **Also known as:** BELL-CVE-2023-54186, DEBIAN-CVE-2023-54186, GHSA-xgf9-7jgm-fgxp, UBUNTU-CVE-2023-54186

## What is CVE-2023-54186?

CVE-2023-54186 is a high-severity use after free vulnerability in Linux, published on 30 Dec 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:

usb: typec: altmodes/displayport: fix pin_assignment_show

This patch fixes negative indexing of buf array in pin_assignment_show
when get_current_pin_assignments returns 0 i.e. no compatible pin
assignments are found.

BUG: KASAN: use-after-free in pin_assignment_show+0x26c/0x33c
...
Call trace:
dump_backtrace+0x110/0x204
dump_stack_lvl+0x84/0xbc
print_report+0x358/0x974
kasan_report+0x9c/0xfc
__do_kernel_fault+0xd4/0x2d4
do_bad_area+0x48/0x168
do_tag_check_fault+0x24/0x38
do_mem_abort+0x6c/0x14c
el1_abort+0x44/0x68
el1h_64_sync_handler+0x64/0xa4
el1h_64_sync+0x78/0x7c
pin_assignment_show+0x26c/0x33c
dev_attr_show+0x50/0xc0

## Which versions are affected by CVE-2023-54186?


## How do I fix CVE-2023-54186?

Apply the vendor's patch.

## Is CVE-2023-54186 being exploited?

There is no known exploitation of CVE-2023-54186 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-54186 and fix it if it is affected.

What it is: CVE-2023-54186 is a high-severity use after free vulnerability in Linux, published on 30 Dec 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-2023-54186 in the wild and no public exploit code.

Affected product: Linux. 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-2023-54186/ (Markdown: https://insights.sbomify.com/CVE-2023-54186/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-54186
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-54186
- OSV: https://osv.dev/vulnerability/CVE-2023-54186

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-54186/
Summaries are generated and may contain mistakes; the official description above is the record.