text/plain and/or text/html. Malicious files or data can be obfuscated and hidden inside of HTML files through Data URLs and/or JavaScript Blobs and can be deobfuscated when they reach the victim (i.e. [Deobfuscate/Decode Files or Information](https://attack.mitre.org/techniques/T1140)), potentially bypassing content filters.
For example, JavaScript Blobs can be abused to dynamically generate malicious files in the victim machine and may be dropped to disk by abusing JavaScript functions such as msSaveBlob.(Citation: HTML Smuggling Menlo Security 2020)(Citation: MSTIC NOBELIUM May 2021)(Citation: Outlflank HTML Smuggling 2018)(Citation: nccgroup Smuggling HTA 2017)
Linked Issues
| Linktype | Issue |
|---|---|
| is related to | Techniques |
| is blocked by | Application Isolation and Sandboxing |
| is blocked by | Detection Strategy for HTML Smuggling via JavaScript Blob + Dynamic File Drop |
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