# CVE-2022-21696: Username spoofing in OnionShare

> Attackers can impersonate other chat participants in OnionShare by appending whitespace to usernames, bypassing identity verification.

- **Severity:** Medium 4.3 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 18 Jan 2022
- **Updated:** 23 Apr 2025
- **Also known as:** DEBIAN-CVE-2022-21696, GHSA-68vr-8f46-vc9f, PYSEC-2022-47

## What is CVE-2022-21696?

CVE-2022-21696 is a medium-severity vulnerability in onionshare, published on 18 Jan 2022. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

OnionShare is an open source tool that lets you securely and anonymously share files, host websites, and chat with friends using the Tor network. In affected versions it is possible to change the username to that of another chat participant with an additional space character at the end of the name string. An adversary with access to the chat environment can use the rename feature to impersonate other participants by adding whitespace characters at the end of the username.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2022-21696?

3 open source packages ship an affected version, including onionshare-cli. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `onionshare-cli` | PyPI | All versions | 2.5 |
| `onionshare-cli` | PyPI | From 2.3 | 2.5 |
| `onionshare-cli` | PyPI | From 2.3 | 2.5 |

Products: Onionshare Onionshare.

## How do I fix CVE-2022-21696?

Upgrade onionshare-cli to 2.5 or later.

## Is CVE-2022-21696 being exploited?

There is no known exploitation of CVE-2022-21696 in the wild and no public exploit code.

## Other vulnerabilities in onionshare

- [CVE-2021-41868](https://insights.sbomify.com/CVE-2021-41868/): Remote unauthenticated attackers able to upload files in Onionshare (critical 9.8)
- [CVE-2022-21690](https://insights.sbomify.com/CVE-2022-21690/): Cross-Site Scripting in Onionshare (high 8.7)
- [CVE-2022-21688](https://insights.sbomify.com/CVE-2022-21688/): Out-of-bounds Read in Onionshare (high 7.5)
- [CVE-2022-21689](https://insights.sbomify.com/CVE-2022-21689/): Denial of Service in Onionshare (high 7.5)
- [CVE-2018-19960](https://insights.sbomify.com/CVE-2018-19960/): Path traversal in n/a (high 7.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-21696 and fix it if it is affected.

What it is: CVE-2022-21696 is a medium-severity vulnerability in onionshare, published on 18 Jan 2022. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2022-21696 in the wild and no public exploit code.

Affected packages and fixed versions:
- onionshare-cli (PyPI): affected all versions; fixed in 2.5
- onionshare-cli (PyPI): affected from 2.3; fixed in 2.5
- onionshare-cli (PyPI): affected from 2.3; fixed in 2.5

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-2022-21696/ (Markdown: https://insights.sbomify.com/CVE-2022-21696/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-21696
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-21696
- OSV: https://osv.dev/vulnerability/CVE-2022-21696

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-21696/
Summaries are generated and may contain mistakes; the official description above is the record.