# CVE-2012-6685: Nokogiri is vulnerable to XML External Entity (XXE) attack

> An attacker can exploit XML External Entity vulnerabilities in Nokogiri to read sensitive files or cause denial of service.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 19 Feb 2020
- **Updated:** 6 Aug 2024
- **Also known as:** DEBIAN-CVE-2012-6685, DLA-229-1, GHSA-6wj9-77wq-jq7p

## What is CVE-2012-6685?

CVE-2012-6685 is a high-severity vulnerability in Redhat Enterprise Mrg, published on 19 Feb 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Nokogiri before 1.5.4 is vulnerable to XXE attacks

Weakness: CWE-776 (Improper Restriction of Recursive Entity References in DTDs)

## Which versions are affected by CVE-2012-6685?

2 open source packages ship an affected version, including nokogiri. It affects 8 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `nokogiri` | RubyGems | All versions | 1.5.4 |
| `nokogiri` | RubyGems | All versions | 1.5.4 |

Products: Nokogiri Nokogiri, Redhat Cloudforms Management Engine, Redhat Enterprise Mrg, Redhat Openshift, Redhat Openstack, Redhat Openstack Foreman, Redhat Satellite, Redhat Subscription Asset Manager.

## How do I fix CVE-2012-6685?

Upgrade nokogiri to 1.5.4 or later.

## Is CVE-2012-6685 being exploited?

There is no known exploitation of CVE-2012-6685 in the wild and no public exploit code.

## Other vulnerabilities in Redhat Enterprise Mrg

- [CVE-2026-79770](https://insights.sbomify.com/CVE-2026-79770/): Nokogiri before 1.19.3 ReDoS via CSS selector tokenizer (high 8.7)
- [CVE-2022-23476](https://insights.sbomify.com/CVE-2022-23476/): Unchecked return value from xmlTextReaderExpand in Nokogiri (high 7.5)
- [CVE-2021-41098](https://insights.sbomify.com/CVE-2021-41098/): Improper Restriction of XML External Entity Reference (XXE) in Nokogiri on JRuby (high 7.5)
- [CVE-2026-79771](https://insights.sbomify.com/CVE-2026-79771/): Nokogiri before 1.19.3 Memory Leak via XSLT Transform (medium 6.9)
- [CVE-2026-79772](https://insights.sbomify.com/CVE-2026-79772/): Nokogiri before 1.19.1 Unchecked Return Value canonicalize (medium 6.9)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2012-6685 and fix it if it is affected.

What it is: CVE-2012-6685 is a high-severity vulnerability in Redhat Enterprise Mrg, published on 19 Feb 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-2012-6685 in the wild and no public exploit code.

Affected packages and fixed versions:
- nokogiri (RubyGems): affected all versions; fixed in 1.5.4
- nokogiri (RubyGems): affected all versions; fixed in 1.5.4

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-2012-6685/ (Markdown: https://insights.sbomify.com/CVE-2012-6685/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2012-6685
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2012-6685
- OSV: https://osv.dev/vulnerability/CVE-2012-6685

---
From sbomify Insights: https://insights.sbomify.com/CVE-2012-6685/
Summaries are generated and may contain mistakes; the official description above is the record.