# CVE-2021-41181: Nextcloud Talk app exposes chat messages on lockscreen

> An attacker with physical access to a locked Android device can view chat messages and files if an incoming call is received.

- **Severity:** Low 2.4 (`CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:L/I:N/A: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:** 8 Mar 2022
- **Updated:** 23 Apr 2025
- **Also known as:** GHSA-497c-c8hx-6qcf

## What is CVE-2021-41181?

CVE-2021-41181 is a low-severity vulnerability in nextcloud security-advisories, published on 8 Mar 2022. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Nextcloud talk is a self hosting messaging service. In versions prior to 12.3.0 the Nextcloud Android Talk application did not properly detect the lockscreen state when a call was incoming. If an attacker got physical access to the locked phone, and the victim received a phone call the attacker could gain access to the chat messages and files of the user. It is recommended that the Nextcloud Android Talk App is upgraded to 12.3.0. There are no known workarounds.

Weakness: CWE-287 (Improper Authentication), CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor)

## Which versions are affected by CVE-2021-41181?

It affects 1 product.


Products: Nextcloud Talk.

## How do I fix CVE-2021-41181?

No fix has been published for CVE-2021-41181 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-41181 being exploited?

There is no known exploitation of CVE-2021-41181 in the wild and no public exploit code.

## Other vulnerabilities in nextcloud security-advisories

- [CVE-2020-8180](https://insights.sbomify.com/CVE-2020-8180/): Code injection in Nextcloud Talk (critical 9.9)
- [CVE-2021-32689](https://insights.sbomify.com/CVE-2021-32689/): Nextcloud Talk not properly disassociating users from chats after account deletion (high 8.1)
- [CVE-2023-39957](https://insights.sbomify.com/CVE-2023-39957/): Path traversal allows tricking the Talk Android app into writing files into it's root directory (high 7.2)
- [CVE-2021-32676](https://insights.sbomify.com/CVE-2021-32676/): Session Fixation in Nextcloud Talk (medium 6.5)
- [CVE-2021-39222](https://insights.sbomify.com/CVE-2021-39222/): XSS in Talk (medium 6.4)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-41181 and fix it if it is affected.

What it is: CVE-2021-41181 is a low-severity vulnerability in nextcloud security-advisories, published on 8 Mar 2022. 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-2021-41181 in the wild and no public exploit code.

Affected product: nextcloud security-advisories. 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-2021-41181/ (Markdown: https://insights.sbomify.com/CVE-2021-41181/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-41181
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-41181
- OSV: https://osv.dev/vulnerability/CVE-2021-41181

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-41181/
Summaries are generated and may contain mistakes; the official description above is the record.