# CVE-2020-24612: Auth bypass in n/a

> An attacker can bypass two-factor authentication by exploiting a SELinux policy flaw that prevents reading U2F configuration files.

- **Severity:** Medium 6.7 (`CVSS:3.1/AC:H/AV:L/A:N/C:H/I:H/PR:N/S:U/UI:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 24 Aug 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-j8gx-8c94-5x9v, OESA-2022-1646, UBUNTU-CVE-2020-24612

## What is CVE-2020-24612?

CVE-2020-24612 is a medium-severity authentication bypass vulnerability in n/a, published on 24 Aug 2020. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

An issue was discovered in the selinux-policy (aka Reference Policy) package 3.14 through 2020-08-24 because the .config/Yubico directory is mishandled. Consequently, when SELinux is in enforced mode, pam-u2f is not allowed to read the user's U2F configuration file. If configured with the nouserok option (the default when configured by the authselect tool), and that file cannot be read, the second factor is disabled. An attacker with only the knowledge of the password can then log in, bypassing 2FA.

Weakness: CWE-287 (Improper Authentication)

## Which versions are affected by CVE-2020-24612?

It affects 1 product.


Products: Fedoraproject Selinux-Policy.

## How do I fix CVE-2020-24612?

Apply the vendor's patch.

## Is CVE-2020-24612 being exploited?

There is no known exploitation of CVE-2020-24612 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-24612 and fix it if it is affected.

What it is: CVE-2020-24612 is a medium-severity authentication bypass vulnerability in n/a, published on 24 Aug 2020. 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-2020-24612 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-2020-24612/ (Markdown: https://insights.sbomify.com/CVE-2020-24612/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-24612
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-24612
- OSV: https://osv.dev/vulnerability/CVE-2020-24612

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From sbomify Insights: https://insights.sbomify.com/CVE-2020-24612/
Summaries are generated and may contain mistakes; the official description above is the record.