# CVE-2009-0642: Security feature bypass in n/a

> Attackers can bypass certificate revocation checks in Ruby's OpenSSL extension by presenting invalid X.509 certificates, undermining TLS security.

- **Severity:** Medium 6.8 (`AV:N/AC:M/Au:N/C:P/I:P/A:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 18 Feb 2009
- **Updated:** 7 Aug 2024
- **Also known as:** GHSA-4gvm-4mw2-9fpv

## What is CVE-2009-0642?

CVE-2009-0642 is a medium-severity vulnerability in Ruby-Lang Ruby, published on 18 Feb 2009. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

ext/openssl/ossl_ocsp.c in Ruby 1.8 and 1.9 does not properly check the return value from the OCSP_basic_verify function, which might allow remote attackers to successfully present an invalid X.509 certificate, possibly involving a revoked certificate.

Weakness: CWE-287 (Improper Authentication)

## Which versions are affected by CVE-2009-0642?

It affects 1 product.


Products: Ruby-Lang Ruby.

## How do I fix CVE-2009-0642?

Upgrade to a fixed version.

## Is CVE-2009-0642 being exploited?

There is no known exploitation of CVE-2009-0642 in the wild and no public exploit code.

## Other vulnerabilities in Ruby-Lang Ruby

- [CVE-2009-4124](https://insights.sbomify.com/CVE-2009-4124/): Memory corruption in n/a (critical 10.0)
- [CVE-2022-28738](https://insights.sbomify.com/CVE-2022-28738/): Use after free in n/a (critical 9.8)
- [CVE-2011-4121](https://insights.sbomify.com/CVE-2011-4121/): Weak cryptography in OpenSSL extension of Ruby (Git trunk) (critical 9.8)
- [CVE-2017-17790](https://insights.sbomify.com/CVE-2017-17790/): Command injection in n/a (critical 9.8)
- [CVE-2017-11465](https://insights.sbomify.com/CVE-2017-11465/): Memory corruption in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2009-0642 and fix it if it is affected.

What it is: CVE-2009-0642 is a medium-severity vulnerability in Ruby-Lang Ruby, published on 18 Feb 2009. 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-2009-0642 in the wild and no public exploit code.

Affected product: Ruby-Lang Ruby. 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-2009-0642/ (Markdown: https://insights.sbomify.com/CVE-2009-0642/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2009-0642
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2009-0642
- OSV: https://osv.dev/vulnerability/CVE-2009-0642

---
From sbomify Insights: https://insights.sbomify.com/CVE-2009-0642/
Summaries are generated and may contain mistakes; the official description above is the record.