# CVE-2021-21400: Entering code in App Lock modal sends input to conversation

> Attackers can steal app-lock passphrases if users type them without focusing the input field, as the text is sent to the active chat.

- **Severity:** High 7.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/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:** 2 Apr 2021
- **Updated:** 3 Aug 2024
- **Also known as:** GHSA-cxwr-f2j3-q8hp

## What is CVE-2021-21400?

CVE-2021-21400 is a high-severity vulnerability in wireapp wire-webapp, published on 2 Apr 2021. 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

wire-webapp is an open-source front end for Wire, a secure collaboration platform. In wire-webapp before version 2021-03-15-production.0, when being prompted to enter the app-lock passphrase, the typed passphrase will be sent into the most recently used chat when the user does not actively give focus to the input field. Input element focus is enforced programatically in version 2021-03-15-production.0.

Weakness: CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor)

## Which versions are affected by CVE-2021-21400?

It affects 1 product.


Products: Wire Wire-Webapp.

## How do I fix CVE-2021-21400?

No fix has been published for CVE-2021-21400 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-21400 being exploited?

There is no known exploitation of CVE-2021-21400 in the wild and no public exploit code.

## Other vulnerabilities in wireapp wire-webapp

- [CVE-2022-29168](https://insights.sbomify.com/CVE-2022-29168/): Cross Site Scripting in Wire Messages (critical 9.6)
- [CVE-2022-24799](https://insights.sbomify.com/CVE-2022-24799/): Cross Site Scripting in Wire Webapp (critical 9.6)
- [CVE-2021-32683](https://insights.sbomify.com/CVE-2021-32683/): XSS through createObjectURL (high 8.8)
- [CVE-2025-48066](https://insights.sbomify.com/CVE-2025-48066/): wire-webapp has no database deletion on client logout (medium 6.0)
- [CVE-2022-39380](https://insights.sbomify.com/CVE-2022-39380/): wire-webapp contains Improper Handling of Exceptional Conditions leading to a DoS via Markdown Rendering (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-21400 and fix it if it is affected.

What it is: CVE-2021-21400 is a high-severity vulnerability in wireapp wire-webapp, published on 2 Apr 2021. 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-2021-21400 in the wild and no public exploit code.

Affected product: wireapp wire-webapp. 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-2021-21400/ (Markdown: https://insights.sbomify.com/CVE-2021-21400/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-21400
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-21400
- OSV: https://osv.dev/vulnerability/CVE-2021-21400

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-21400/
Summaries are generated and may contain mistakes; the official description above is the record.