# CVE-2026-34120: Heap-based Buffer Overflow Vulnerability Leading to Denial-of-Service in TP-Link Tapo C520WS

> An attacker on the same network can cause a denial-of-service condition in TP-Link Tapo C520WS cameras by triggering a heap-based buffer overflow via crafted video stream payloads.

- **Severity:** High 7.1 (`CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 2 Apr 2026
- **Updated:** 2 Apr 2026
- **Also known as:** GHSA-m7f4-p6pg-38mf

## What is CVE-2026-34120?

CVE-2026-34120 is a high-severity memory corruption vulnerability in TP-Link Systems Inc. Tapo C520WS v2.6, published on 2 Apr 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A heap-based buffer overflow vulnerability was identified in TP-Link Tapo C520WS v2.6 within the asynchronous parsing of local video stream content due to
insufficient alignment and validation of buffer boundaries when processing streaming inputs.An attacker
on the same network segment could trigger heap memory corruption conditions by
sending crafted payloads that cause write operations beyond allocated buffer
boundaries.  Successful exploitation
causes a Denial-of-Service (DoS) condition, causing the device’s process to
crash or become unresponsive.

Weakness: CWE-122 (Heap-based Buffer Overflow)

## Which versions are affected by CVE-2026-34120?

It affects 1 product.


Products: Tp-Link Tapo C520ws Firmware.

## How do I fix CVE-2026-34120?

No fix has been published for CVE-2026-34120 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-34120 being exploited?

There is no known exploitation of CVE-2026-34120 in the wild and no public exploit code.

## Other vulnerabilities in TP-Link Systems Inc. Tapo C520WS v2.6

- [CVE-2026-34121](https://insights.sbomify.com/CVE-2026-34121/): Authentication Bypass in DS Configuration Service via HTTP Request Parsing Differential of TP-Link Tapo C520WS (high 8.7)
- [CVE-2026-8714](https://insights.sbomify.com/CVE-2026-8714/): Denial-of-Service Vulnerability in RTSP Input Handling on TP-Link's Tapo C520WS (high 7.1)
- [CVE-2026-34118](https://insights.sbomify.com/CVE-2026-34118/): Heap-based Buffer Overflow Vulnerability Leading to Denial-of-Service in TP-Link Tapo C100, C101, C210 & C520WS (high 7.1)
- [CVE-2026-34119](https://insights.sbomify.com/CVE-2026-34119/): Heap-based Buffer Overflow Vulnerability Leading to Denial-of-Service in TP-Link Tapo C520WS (high 7.1)
- [CVE-2026-34122](https://insights.sbomify.com/CVE-2026-34122/): Stack-based Buffer Overflow Leading to Denial of Service in TP-Link Tapo C520WS (high 7.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-34120 and fix it if it is affected.

What it is: CVE-2026-34120 is a high-severity memory corruption vulnerability in TP-Link Systems Inc. Tapo C520WS v2.6, published on 2 Apr 2026. 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-2026-34120 in the wild and no public exploit code.

Affected product: TP-Link Systems Inc. Tapo C520WS v2.6. 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-2026-34120/ (Markdown: https://insights.sbomify.com/CVE-2026-34120/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-34120
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-34120
- OSV: https://osv.dev/vulnerability/CVE-2026-34120

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-34120/
Summaries are generated and may contain mistakes; the official description above is the record.