# CVE-2015-2694: Auth bypass in n/a

> Remote attackers can bypass Kerberos preauthentication requirements by sending empty data or arbitrary realm names, potentially gaining unauthorized access.

- **Severity:** Medium 5.8 (`AV:N/AC:M/Au:N/C:P/I:P/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:** 25 May 2015
- **Updated:** 6 Aug 2024
- **Also known as:** DEBIAN-CVE-2015-2694, GHSA-6h2g-5cjr-jj97, UBUNTU-CVE-2015-2694

## What is CVE-2015-2694?

CVE-2015-2694 is a medium-severity authentication bypass vulnerability in Mit Kerberos 5, published on 25 May 2015. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The kdcpreauth modules in MIT Kerberos 5 (aka krb5) 1.12.x and 1.13.x before 1.13.2 do not properly track whether a client's request has been validated, which allows remote attackers to bypass an intended preauthentication requirement by providing (1) zero bytes of data or (2) an arbitrary realm name, related to plugins/preauth/otp/main.c and plugins/preauth/pkinit/pkinit_srv.c.

Weakness: CWE-264

## Which versions are affected by CVE-2015-2694?

It affects 1 product.


Products: Mit Kerberos 5.

## How do I fix CVE-2015-2694?

Upgrade to a fixed version.

## Is CVE-2015-2694 being exploited?

There is no known exploitation of CVE-2015-2694 in the wild and no public exploit code.

## Other vulnerabilities in Mit Kerberos 5

- [CVE-2011-0285](https://insights.sbomify.com/CVE-2011-0285/): Use after free in n/a (critical 10.0)
- [CVE-2008-0947](https://insights.sbomify.com/CVE-2008-0947/): Memory corruption in n/a (critical 10.0)
- [CVE-2007-5902](https://insights.sbomify.com/CVE-2007-5902/): Integer overflow in n/a (critical 10.0)
- [CVE-2007-4743](https://insights.sbomify.com/CVE-2007-4743/): Memory corruption in n/a (critical 10.0)
- [CVE-2007-3999](https://insights.sbomify.com/CVE-2007-3999/): Memory corruption in n/a (critical 10.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2015-2694 and fix it if it is affected.

What it is: CVE-2015-2694 is a medium-severity authentication bypass vulnerability in Mit Kerberos 5, published on 25 May 2015. 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-2015-2694 in the wild and no public exploit code.

Affected product: Mit Kerberos 5. 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-2015-2694/ (Markdown: https://insights.sbomify.com/CVE-2015-2694/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2015-2694
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2015-2694
- OSV: https://osv.dev/vulnerability/CVE-2015-2694

---
From sbomify Insights: https://insights.sbomify.com/CVE-2015-2694/
Summaries are generated and may contain mistakes; the official description above is the record.