# CVE-2019-19194: Auth bypass in n/a

> Attackers can bypass Bluetooth pairing security to read, modify, or crash devices due to a zero long term key vulnerability in the Telink BLE SDK.

- **Severity:** High 8.8 (`CVSS:3.1/AV:A/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:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 12 Feb 2020
- **Updated:** 5 Aug 2024
- **Also known as:** GHSA-98r9-mgjw-46jp

## What is CVE-2019-19194?

CVE-2019-19194 is a high-severity authentication bypass vulnerability in n/a, published on 12 Feb 2020. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

The Bluetooth Low Energy Secure Manager Protocol (SMP) implementation on Telink Semiconductor BLE SDK versions before November 2019 for TLSR8x5x through 3.4.0, TLSR823x through 1.3.0, and TLSR826x through 3.3 devices installs a zero long term key (LTK) if an out-of-order link-layer encryption request is received during Secure Connections pairing. An attacker in radio range can have arbitrary read/write access to protected GATT service data, cause a device crash, or possibly control a device's function by establishing an encrypted session with the zero LTK.

## Which versions are affected by CVE-2019-19194?

It affects 5 products.


Products: Telink-Semi Tlsr8232 Ble Sdk, Telink-Semi Tlsr8251 Ble Sdk, Telink-Semi Tlsr8253 Ble Sdk, Telink-Semi Tlsr8258 Ble Sdk, Telink-Semi Tlsr8269 Ble Sdk.

## How do I fix CVE-2019-19194?

No fix has been published for CVE-2019-19194 yet. Limit exposure of the affected software until one is available.

## Is CVE-2019-19194 being exploited?

There is no known exploitation of CVE-2019-19194 in the wild and no public exploit code.

Public exploit code:

- A writeup and theoretical Proof-of-Concept for CVE-2019-19194 (github_poc): https://github.com/louisabricot/writeup-cve-2019-19194

## Other vulnerabilities in n/a

- [CVE-2019-19196](https://insights.sbomify.com/CVE-2019-19196/): Memory corruption in n/a (medium 6.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-19194 and fix it if it is affected.

What it is: CVE-2019-19194 is a high-severity authentication bypass vulnerability in n/a, published on 12 Feb 2020. 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-2019-19194 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-2019-19194/ (Markdown: https://insights.sbomify.com/CVE-2019-19194/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-19194
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-19194
- OSV: https://osv.dev/vulnerability/CVE-2019-19194

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-19194/
Summaries are generated and may contain mistakes; the official description above is the record.