# CVE-2023-36340: Memory corruption in n/a

> A stack overflow in the loginAuth function allows attackers to execute arbitrary code or cause denial of service on TOTOLINK NR1800X routers.

- **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:** 16 Oct 2023
- **Updated:** 16 Sep 2024
- **Also known as:** GHSA-ff5g-xv9r-r383

## What is CVE-2023-36340?

CVE-2023-36340 is a critical memory corruption vulnerability in n/a, published on 16 Oct 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

TOTOLINK NR1800X V9.1.0u.6279_B20210910 was discovered to contain a stack overflow via the http_host parameter in the function loginAuth.

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2023-36340?

It affects 1 product.


Products: Totolink Nr1800x Firmware.

## How do I fix CVE-2023-36340?

No fix has been published for CVE-2023-36340 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-36340 being exploited?

There is no known exploitation of CVE-2023-36340 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2023-7220](https://insights.sbomify.com/CVE-2023-7220/): Totolink NR1800X cstecgi.cgi loginAuth stack-based overflow (critical 9.8)
- [CVE-2022-41518](https://insights.sbomify.com/CVE-2022-41518/): Command injection in n/a (critical 9.8)
- [CVE-2022-41522](https://insights.sbomify.com/CVE-2022-41522/): Memory corruption in n/a (critical 9.8)
- [CVE-2022-41525](https://insights.sbomify.com/CVE-2022-41525/): Command injection in n/a (critical 9.8)
- [CVE-2025-45842](https://insights.sbomify.com/CVE-2025-45842/): Memory corruption in n/a (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-36340 and fix it if it is affected.

What it is: CVE-2023-36340 is a critical memory corruption vulnerability in n/a, published on 16 Oct 2023. 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-2023-36340 in the wild and no public exploit code.

Affected product: n/a. 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-2023-36340/ (Markdown: https://insights.sbomify.com/CVE-2023-36340/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-36340
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-36340
- OSV: https://osv.dev/vulnerability/CVE-2023-36340

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-36340/
Summaries are generated and may contain mistakes; the official description above is the record.