# CVE-2021-40526: Memory corruption in n/a

> Remote attackers can cause a denial of service on Peleton Bikes by triggering a heap overflow in the GymKit daemon, preventing device authentication.

- **Severity:** Medium 4.8 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 25 Oct 2021
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-jvqh-h8m5-xc3q

## What is CVE-2021-40526?

CVE-2021-40526 is a medium-severity memory corruption vulnerability in n/a, published on 25 Oct 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Incorrect calculation of buffer size vulnerability in Peleton TTR01 up to and including PTV55G allows a remote attacker to trigger a Denial of Service attack through the GymKit daemon process by exploiting a heap overflow in the network server handling the Apple GymKit communication. This can lead to an Apple MFI device not being able to authenticate with the Peleton Bike

Weakness: CWE-131 (Incorrect Calculation of Buffer Size)

## Which versions are affected by CVE-2021-40526?

It affects 1 product.


Products: Onepeloton Ttr01 Firmware.

## How do I fix CVE-2021-40526?

No fix has been published for CVE-2021-40526 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-40526 being exploited?

There is no known exploitation of CVE-2021-40526 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2021-33887](https://insights.sbomify.com/CVE-2021-33887/): Security feature bypass in n/a (medium 6.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-40526 and fix it if it is affected.

What it is: CVE-2021-40526 is a medium-severity memory corruption vulnerability in n/a, published on 25 Oct 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-2021-40526 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-2021-40526/ (Markdown: https://insights.sbomify.com/CVE-2021-40526/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-40526
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-40526
- OSV: https://osv.dev/vulnerability/CVE-2021-40526

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-40526/
Summaries are generated and may contain mistakes; the official description above is the record.