# CVE-2020-7659: HTTP Request Smuggling in reel

> Attackers can perform HTTP request smuggling via header parsing flaws in the deprecated Reel Ruby web framework, potentially bypassing security controls.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 1 Jun 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-x3v4-pxvm-63j8, SNYK-RUBY-REEL-569135, UBUNTU-CVE-2020-7659

## What is CVE-2020-7659?

CVE-2020-7659 is a high-severity vulnerability in reel, published on 1 Jun 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

reel through 0.6.1 allows Request Smuggling attacks due to incorrect Content-Length and Transfer encoding header parsing. It is possible to conduct HTTP request smuggling attacks by sending the Content-Length header twice. Furthermore, invalid Transfer Encoding headers were found to be parsed as valid which could be leveraged for TE:CL smuggling attacks. Note: This project is deprecated, and is not maintained any more.

Weakness: CWE-444 (Inconsistent Interpretation of HTTP Requests)

## Which versions are affected by CVE-2020-7659?

2 open source packages ship an affected version, including reel. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `reel` | RubyGems | All versions to 0.6.1 | None |
| `reel` | RubyGems | All versions to 0.6.1 | None |

Products: Celluloid Reel.

## How do I fix CVE-2020-7659?

No fix has been published for CVE-2020-7659 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-7659 being exploited?

There is no known exploitation of CVE-2020-7659 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-7659 and fix it if it is affected.

What it is: CVE-2020-7659 is a high-severity vulnerability in reel, published on 1 Jun 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2020-7659 in the wild and no public exploit code.

Affected packages and fixed versions:
- reel (RubyGems): affected all versions up to 0.6.1; no fix listed
- reel (RubyGems): affected all versions up to 0.6.1; no fix listed

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-2020-7659/ (Markdown: https://insights.sbomify.com/CVE-2020-7659/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-7659
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-7659
- OSV: https://osv.dev/vulnerability/CVE-2020-7659

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-7659/
Summaries are generated and may contain mistakes; the official description above is the record.