> For the complete documentation index, see [llms.txt](https://heinosass.gitbook.io/leet-sheet/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://heinosass.gitbook.io/leet-sheet/web-app-hacking/server-attacks/parser-inconsistencies.md).

# Parser Inconsistencies

When different parsers parse the same input differently, then application logic vulnerabilities can occur.

## JSON Interoperability Vulnerabilities

Excellent article:

{% embed url="<https://bishopfox.com/blog/json-interoperability-vulnerabilities>" %}

## URL Interoperability Vulnerabilities

Orange Tsai had an excellent presentation about that:

<https://www.blackhat.com/docs/us-17/thursday/us-17-Tsai-A-New-Era-Of-SSRF-Exploiting-URL-Parser-In-Trending-Programming-Languages.pdf>