# PSF-2017-11: Expat 2.2.3

> Expat library contains a DLL hijacking vulnerability on Windows allowing attackers to execute arbitrary code or escalate privileges.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 17 Jul 2017

## What is PSF-2017-11?

PSF-2017-11 is a vulnerability, published on 17 Jul 2017. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Expat 2.2.2 was released with multiple security fixes:

* #43: Protect against compilation without any source of high quality
  entropy enabled, e.g. with CMake build system
* #60: Windows with _UNICODE: Unintended use of LoadLibraryW with a non-wide
  string resulted in failure to load advapi32.dll and degradation in quality
  of used entropy when compiled with _UNICODE for Windows; you can launch
  existing binaries with EXPAT_ENTROPY_DEBUG=1 in the environment to inspect
  the quality of entropy used during runtime
* [MOX-006]: Fix non-NULL parser parameter validation in XML_Parse; resulted
  in NULL dereference, previously

Expat 2.2.3 contains an additional security fix: #82: CVE-2017-11742 --
Windows: Fix DLL hijacking vulnerability using Steve Holme's LoadLibrary
wrapper for/of cURL

## Which versions are affected by PSF-2017-11?


## How do I fix PSF-2017-11?

No fix has been published for PSF-2017-11 yet. Limit exposure of the affected software until one is available.

## Is PSF-2017-11 being exploited?

There is no known exploitation of PSF-2017-11 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for PSF-2017-11 and fix it if it is affected.

What it is: PSF-2017-11 is a vulnerability, published on 17 Jul 2017. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of PSF-2017-11 in the wild and no public exploit code.

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/PSF-2017-11/ (Markdown: https://insights.sbomify.com/PSF-2017-11/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/PSF-2017-11

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From sbomify Insights: https://insights.sbomify.com/PSF-2017-11/
Summaries are generated and may contain mistakes; the official description above is the record.