# CVE-2017-0911: Auth bypass in Twitter Kit for iOS

> Attackers can forge authentication callbacks to associate Twitter accounts with third-party services due to missing response verification in the login flow.

- **Severity:** Medium 5.4 (`CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/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:** No
- **Published:** 9 Feb 2018
- **Updated:** 17 Sep 2024
- **Also known as:** GHSA-rcwq-7c2v-mc74

## What is CVE-2017-0911?

CVE-2017-0911 is a medium-severity authentication bypass vulnerability in Twitter Kit for iOS, published on 9 Feb 2018. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Twitter Kit for iOS versions 3.0 to 3.2.1 is vulnerable to a callback verification flaw in the "Login with Twitter" component allowing an attacker to provide alternate credentials. In the final step of "Login with Twitter" authentication information is passed back to the application using the registered custom URL scheme (typically twitterkit-<consumer-key>) on iOS. Because the callback handler did not verify the authenticity of the response, this step is vulnerable to forgery, potentially allowing attacker to associate a Twitter account with a third-party service.

Weakness: CWE-287 (Improper Authentication), CWE-360 (Trust of System Event Data)

## Which versions are affected by CVE-2017-0911?

It affects 1 product.


Products: Twitter Twitter Kit.

## How do I fix CVE-2017-0911?

No fix has been published for CVE-2017-0911 yet. Limit exposure of the affected software until one is available.

## Is CVE-2017-0911 being exploited?

There is no known exploitation of CVE-2017-0911 in the wild and no public exploit code.

## Other vulnerabilities in Twitter Kit for iOS

- [CVE-2019-16263](https://insights.sbomify.com/CVE-2019-16263/): Weak cryptography in n/a (high 7.4)
- [CVE-2019-5431](https://insights.sbomify.com/CVE-2019-5431/): Auth bypass in Twitter Kit for iOS (medium 5.4)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2017-0911 and fix it if it is affected.

What it is: CVE-2017-0911 is a medium-severity authentication bypass vulnerability in Twitter Kit for iOS, published on 9 Feb 2018. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2017-0911 in the wild and no public exploit code.

Affected product: Twitter Kit for iOS. 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-2017-0911/ (Markdown: https://insights.sbomify.com/CVE-2017-0911/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2017-0911
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2017-0911
- OSV: https://osv.dev/vulnerability/CVE-2017-0911

---
From sbomify Insights: https://insights.sbomify.com/CVE-2017-0911/
Summaries are generated and may contain mistakes; the official description above is the record.