# CVE-2011-4973: Auth bypass in n/a

> Remote attackers can bypass authentication in mod_nss by using a valid certificate with the password 'password', leading to account takeover.

- **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:** Yes
- **Published:** 15 Feb 2018
- **Updated:** 7 Aug 2024
- **Also known as:** GHSA-mmjq-r7xw-fqr8, RHBA-2011:1656, RHBA-2013:0009, UBUNTU-CVE-2011-4973

## What is CVE-2011-4973?

CVE-2011-4973 is a critical authentication bypass vulnerability in n/a, published on 15 Feb 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Authentication bypass vulnerability in mod_nss 1.0.8 allows remote attackers to assume the identity of a valid user by using their certificate and entering 'password' as the password.

Weakness: CWE-287 (Improper Authentication)

## Which versions are affected by CVE-2011-4973?

It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `mod_nss` | Red Hat:enterprise_linux:5::client | All versions | 0:1.0.8-7.el5 |
| `mod_nss-debuginfo` | Red Hat:enterprise_linux:5::client | All versions | 0:1.0.8-7.el5 |
| `mod_nss` | Red Hat:enterprise_linux:5::server | All versions | 0:1.0.8-7.el5 |
| `mod_nss-debuginfo` | Red Hat:enterprise_linux:5::server | All versions | 0:1.0.8-7.el5 |
| `mod_nss` | Red Hat:enterprise_linux:6::client | All versions | 0:1.0.8-13.el6 |
| `mod_nss-debuginfo` | Red Hat:enterprise_linux:6::client | All versions | 0:1.0.8-13.el6 |
| `mod_nss` | Red Hat:enterprise_linux:6::computenode | All versions | 0:1.0.8-13.el6 |
| `mod_nss-debuginfo` | Red Hat:enterprise_linux:6::computenode | All versions | 0:1.0.8-13.el6 |
| `mod_nss` | Red Hat:enterprise_linux:6::server | All versions | 0:1.0.8-13.el6 |
| `mod_nss-debuginfo` | Red Hat:enterprise_linux:6::server | All versions | 0:1.0.8-13.el6 |
| `mod_nss` | Red Hat:enterprise_linux:6::workstation | All versions | 0:1.0.8-13.el6 |
| `mod_nss-debuginfo` | Red Hat:enterprise_linux:6::workstation | All versions | 0:1.0.8-13.el6 |

Products: Mod Nss Project Mod Nss.

## How do I fix CVE-2011-4973?

Apply the vendor's patch.

## Is CVE-2011-4973 being exploited?

There is no known exploitation of CVE-2011-4973 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2015-5244](https://insights.sbomify.com/CVE-2015-5244/): Security feature bypass in n/a (critical 9.8)
- [CVE-2015-3277](https://insights.sbomify.com/CVE-2015-3277/): Information disclosure in n/a (high 7.5)
- [CVE-2013-4566](https://insights.sbomify.com/CVE-2013-4566/): Auth bypass in n/a (medium 4.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2011-4973 and fix it if it is affected.

What it is: CVE-2011-4973 is a critical authentication bypass vulnerability in n/a, published on 15 Feb 2018. 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-2011-4973 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-2011-4973/ (Markdown: https://insights.sbomify.com/CVE-2011-4973/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2011-4973
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2011-4973
- OSV: https://osv.dev/vulnerability/CVE-2011-4973

---
From sbomify Insights: https://insights.sbomify.com/CVE-2011-4973/
Summaries are generated and may contain mistakes; the official description above is the record.