# CVE-2020-28877: Memory corruption in n/a

> A buffer overflow in TP-Link routers allows attackers to execute arbitrary code or cause a denial of service via the devDiscoverHandle server.

- **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:** 20 Nov 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-9645-cj65-jfjp

## What is CVE-2020-28877?

CVE-2020-28877 is a critical memory corruption vulnerability in n/a, published on 20 Nov 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Buffer overflow in in the copy_msg_element function for the devDiscoverHandle server in the TP-Link WR and WDR series, including WDR7400, WDR7500, WDR7660, WDR7800, WDR8400, WDR8500, WDR8600, WDR8620, WDR8640, WDR8660, WR880N, WR886N, WR890N, WR890N, WR882N, and WR708N.

Weakness: CWE-120 (Buffer Copy without Checking Size of Input)

## Which versions are affected by CVE-2020-28877?

It affects 15 products.


Products: Tp-Link Wdr7400 Firmware, Tp-Link Wdr7500 Firmware, Tp-Link Wdr7660 Firmware, Tp-Link Wdr7800 Firmware, Tp-Link Wdr8400 Firmware, Tp-Link Wdr8500 Firmware, Tp-Link Wdr8600 Firmware, Tp-Link Wdr8620 Firmware, Tp-Link Wdr8640 Firmware, Tp-Link Wdr8660 Firmware, Tp-Link Wr708n Firmware, Tp-Link Wr880n Firmware, Tp-Link Wr882n Firmware, Tp-Link Wr886n Firmware, Tp-Link Wr890n Firmware.

## How do I fix CVE-2020-28877?

No fix has been published for CVE-2020-28877 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-28877 being exploited?

There is no known exploitation of CVE-2020-28877 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-28877 and fix it if it is affected.

What it is: CVE-2020-28877 is a critical memory corruption vulnerability in n/a, published on 20 Nov 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-2020-28877 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-2020-28877/ (Markdown: https://insights.sbomify.com/CVE-2020-28877/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-28877
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-28877
- OSV: https://osv.dev/vulnerability/CVE-2020-28877

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-28877/
Summaries are generated and may contain mistakes; the official description above is the record.