# CVE-2021-20698: Command injection in C431

> Attackers can execute remote code and gain root privileges on Sharp NEC displays by sending malicious HTTP requests with specific characters.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 7 Jun 2021
- **Updated:** 8 Dec 2025
- **Also known as:** GHSA-xwcc-427v-vm78

## What is CVE-2021-20698?

CVE-2021-20698 is a critical command injection vulnerability in Sharp Display Solutions, Ltd. C431, published on 7 Jun 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Sharp NEC Displays (UN462A R1.300 and prior to it, UN462VA R1.300 and prior to it, UN492S R1.300 and prior to it, UN492VS R1.300 and prior to it, UN552A R1.300 and prior to it, UN552S R1.300 and prior to it, UN552VS R1.300 and prior to it, UN552 R1.300 and prior to it, UN552V R1.300 and prior to it, UX552S R1.300 and prior to it, UX552 R1.300 and prior to it, V864Q R2.000 and prior to it, C861Q R2.000 and prior to it, P754Q R2.000 and prior to it, V754Q R2.000 and prior to it, C751Q R2.000 and prior to it, V984Q R2.000 and prior to it, C981Q R2.000 and prior to it, P654Q R2.000 and prior to it, V654Q R2.000 and prior to it, C651Q R2.000 and prior to it, V554Q R2.000 and prior to it, P404 R3.200 and prior to it, P484 R3.200 and prior to it, P554 R3.200 and prior to it, V404 R3.200 and prior to it, V484 R3.200 and prior to it, V554 R3.200 and prior to it, V404-T R3.200 and prior to it, V484-T R3.200 and prior to it, V554-T R3.200 and prior to it, C501 R2.000 and prior to it, C551 R2.000 and prior to it, C431 R2.000 and prior to it) allows an attacker to obtain root privileges and execute remote code by sending unintended parameters that contain specific characters in http request.

## Which versions are affected by CVE-2021-20698?

It affects 34 products.


Products: Sharp-Nec-Displays C431 Firmware, Sharp-Nec-Displays C501 Firmware, Sharp-Nec-Displays C551 Firmware, Sharp-Nec-Displays C651q Firmware, Sharp-Nec-Displays C751q Firmware, Sharp-Nec-Displays C861q Firmware, Sharp-Nec-Displays C981q Firmware, Sharp-Nec-Displays P404 Firmware, Sharp-Nec-Displays P484 Firmware, Sharp-Nec-Displays P554 Firmware, Sharp-Nec-Displays P654q Firmware, Sharp-Nec-Displays P754q Firmware, Sharp-Nec-Displays Un462a Firmware, Sharp-Nec-Displays Un462va Firmware, Sharp-Nec-Displays Un492s Firmware, Sharp-Nec-Displays Un492vs Firmware, Sharp-Nec-Displays Un552 Firmware, Sharp-Nec-Displays Un552a Firmware, Sharp-Nec-Displays Un552s Firmware, Sharp-Nec-Displays Un552v Firmware and 14 more.

## How do I fix CVE-2021-20698?

No fix has been published for CVE-2021-20698 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-20698 being exploited?

There is no known exploitation of CVE-2021-20698 in the wild and no public exploit code.

## Other vulnerabilities in Sharp Display Solutions, Ltd. C431

- [CVE-2021-20699](https://insights.sbomify.com/CVE-2021-20699/): Command injection in C431 (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-20698 and fix it if it is affected.

What it is: CVE-2021-20698 is a critical command injection vulnerability in Sharp Display Solutions, Ltd. C431, published on 7 Jun 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-20698 in the wild and no public exploit code.

Affected product: Sharp Display Solutions, Ltd. C431. 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-2021-20698/ (Markdown: https://insights.sbomify.com/CVE-2021-20698/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-20698
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-20698
- OSV: https://osv.dev/vulnerability/CVE-2021-20698

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-20698/
Summaries are generated and may contain mistakes; the official description above is the record.