# CVE-2020-15636: Memory corruption in Multiple Routers

> Remote attackers can execute arbitrary code as root on NETGEAR routers via a stack buffer overflow in the check_ra service without authentication.

- **Severity:** High 8.1 (`CVSS:3.0/AV:N/AC:H/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:** 19 Aug 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-4789-cr7h-xx57

## What is CVE-2020-15636?

CVE-2020-15636 is a high-severity memory corruption vulnerability in Netgear R6700 Firmware, published on 19 Aug 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

This vulnerability allows remote attackers to execute arbitrary code on affected installations of NETGEAR R6400, R6700, R7000, R7850, R7900, R8000, RS400, and XR300 routers with firmware 1.0.4.84_10.0.58. Authentication is not required to exploit this vulnerability. The specific flaw exists within the check_ra service. A crafted raePolicyVersion in a RAE_Policy.json file can trigger an overflow of a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-9852.

Weakness: CWE-121 (Stack-based Buffer Overflow)

## Which versions are affected by CVE-2020-15636?

It affects 1 product.


Products: Netgear R6700 Firmware.

## How do I fix CVE-2020-15636?

No fix has been published for CVE-2020-15636 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-15636 being exploited?

There is no known exploitation of CVE-2020-15636 in the wild and no public exploit code.

## Other vulnerabilities in Netgear R6700 Firmware

- [CVE-2023-30280](https://insights.sbomify.com/CVE-2023-30280/): Memory corruption in n/a (critical 9.8)
- [CVE-2021-20173](https://insights.sbomify.com/CVE-2021-20173/): Command injection in Netgear Nighthawk R6700 (high 8.8)
- [CVE-2021-45732](https://insights.sbomify.com/CVE-2021-45732/): Hardcoded credentials in Netgear Nighthawk R6700 (high 8.8)
- [CVE-2020-15635](https://insights.sbomify.com/CVE-2020-15635/): Memory corruption in R6700 (high 8.8)
- [CVE-2020-10924](https://insights.sbomify.com/CVE-2020-10924/): Memory corruption in R6700 (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-15636 and fix it if it is affected.

What it is: CVE-2020-15636 is a high-severity memory corruption vulnerability in Netgear R6700 Firmware, published on 19 Aug 2020. 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-2020-15636 in the wild and no public exploit code.

Affected product: Netgear R6700 Firmware. 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-2020-15636/ (Markdown: https://insights.sbomify.com/CVE-2020-15636/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-15636
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-15636
- OSV: https://osv.dev/vulnerability/CVE-2020-15636

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-15636/
Summaries are generated and may contain mistakes; the official description above is the record.