# CVE-2019-9970: Other in n/a

> Attackers can spoof URLs using IDN homographs in Signal messages, tricking users into clicking malicious links due to visual character similarity.

- **Severity:** Medium 6.5 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 24 Mar 2019
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-9p53-vpmw-2w5c

## What is CVE-2019-9970?

CVE-2019-9970 is a medium-severity vulnerability in n/a, published on 24 Mar 2019. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

Open Whisper Signal (aka Signal-Desktop) through 1.23.1 and the Signal Private Messenger application through 4.35.3 for Android are vulnerable to an IDN homograph attack when displaying messages containing URLs. This occurs because the application produces a clickable link even if (for example) Latin and Cyrillic characters exist in the same domain name, and the available font has an identical representation of characters from different alphabets.

## Which versions are affected by CVE-2019-9970?

It affects 2 products.


Products: Signal Private Messenger, Signal Signal-Desktop.

## How do I fix CVE-2019-9970?

No fix has been published for CVE-2019-9970 yet. Limit exposure of the affected software until one is available.

## Is CVE-2019-9970 being exploited?

There is no known exploitation of CVE-2019-9970 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2019-17192](https://insights.sbomify.com/CVE-2019-17192/): Denial of service in n/a (critical 9.8)
- [CVE-2019-17191](https://insights.sbomify.com/CVE-2019-17191/): Security feature bypass in n/a (high 7.5)
- [CVE-2020-5753](https://insights.sbomify.com/CVE-2020-5753/): Information disclosure in Signal Private Messenger (medium 5.3)
- [CVE-2018-3988](https://insights.sbomify.com/CVE-2018-3988/): Information disclosure in Signal (low 3.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-9970 and fix it if it is affected.

What it is: CVE-2019-9970 is a medium-severity vulnerability in n/a, published on 24 Mar 2019. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2019-9970 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-2019-9970/ (Markdown: https://insights.sbomify.com/CVE-2019-9970/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-9970
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-9970
- OSV: https://osv.dev/vulnerability/CVE-2019-9970

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-9970/
Summaries are generated and may contain mistakes; the official description above is the record.