# CVE-2017-18365: Deserialization in n/a

> Unauthenticated attackers can execute arbitrary code on GitHub Enterprise by exploiting a deserialization flaw in the Management Console using a hardcoded secret.

- **Severity:** Critical 9.8 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 28 Mar 2019
- **Updated:** 5 Aug 2024
- **Also known as:** GHSA-cg2q-c8hj-pqc3

## What is CVE-2017-18365?

CVE-2017-18365 is a critical unsafe deserialization vulnerability in n/a, published on 28 Mar 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The Management Console in GitHub Enterprise 2.8.x before 2.8.7 has a deserialization issue that allows unauthenticated remote attackers to execute arbitrary code. This occurs because the enterprise session secret is always the same, and can be found in the product's source code. By sending a crafted cookie signed with this secret, one can call Marshal.load with arbitrary data, which is a problem because the Marshal data format allows Ruby objects.

Weakness: CWE-502 (Deserialization of Untrusted Data)

## Which versions are affected by CVE-2017-18365?

It affects 1 product.


Products: Github Github.

## How do I fix CVE-2017-18365?

No fix has been published for CVE-2017-18365 yet. Limit exposure of the affected software until one is available.

## Is CVE-2017-18365 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2017-18365 exists.

Public exploit code:

- Github Enterprise Default Session Secret And Deserialization Vulnerability (metasploit)

## Other vulnerabilities in n/a

- [CVE-2020-10516](https://insights.sbomify.com/CVE-2020-10516/): Improper access control in GitHub Enterprise Server leading to privilege escalation of organization member (critical 9.8)
- [CVE-2020-10519](https://insights.sbomify.com/CVE-2020-10519/): Unsafe configuration options in GitHub Pages leading to remote code execution on GitHub Enterprise Server (high 8.8)
- [CVE-2020-10518](https://insights.sbomify.com/CVE-2020-10518/): Unsafe configuration options in GitHub Pages leading to remote code execution on GitHub Enterprise Server (high 8.8)
- [CVE-2021-22863](https://insights.sbomify.com/CVE-2021-22863/): Missing authorization in GitHub Enterprise Server (high 8.1)
- [CVE-2012-2055](https://insights.sbomify.com/CVE-2012-2055/): Missing authorization in n/a (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2017-18365 and fix it if it is affected.

What it is: CVE-2017-18365 is a critical unsafe deserialization vulnerability in n/a, published on 28 Mar 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2017-18365 exists.

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-2017-18365/ (Markdown: https://insights.sbomify.com/CVE-2017-18365/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2017-18365
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2017-18365
- OSV: https://osv.dev/vulnerability/CVE-2017-18365

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From sbomify Insights: https://insights.sbomify.com/CVE-2017-18365/
Summaries are generated and may contain mistakes; the official description above is the record.