cve/2013/CVE-2013-0340.md

### [CVE-2013-0340](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2013-0340)
![](https://img.shields.io/static/v1?label=Product&message=n%2Fa&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=%3D%20n%2Fa%20&color=brighgreen)
![](https://img.shields.io/static/v1?label=Vulnerability&message=n%2Fa&color=brighgreen)

### Description

expat 2.1.0 and earlier does not properly handle entities expansion unless an application developer uses the XML_SetEntityDeclHandler function, which allows remote attackers to cause a denial of service (resource consumption), send HTTP requests to intranet servers, or read arbitrary files via a crafted XML document, aka an XML External Entity (XXE) issue. NOTE: it could be argued that because expat already provides the ability to disable external entity expansion, the responsibility for resolving this issue lies with application developers; according to this argument, this entry should be REJECTed, and each affected application would need its own CVE.

### POC

#### Reference
- http://seclists.org/fulldisclosure/2021/Sep/33
- http://seclists.org/fulldisclosure/2021/Sep/34
- http://seclists.org/fulldisclosure/2021/Sep/35
- http://seclists.org/fulldisclosure/2021/Sep/38
- http://seclists.org/fulldisclosure/2021/Sep/39

#### Github
- https://github.com/ARPSyndicate/cvemon
- https://github.com/NathanielAPawluk/sec-buddy
- https://github.com/fokypoky/places-list
- https://github.com/tiran/defusedxml
- https://github.com/vulsio/gost