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marked npm module "heading" ReDoS

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marked npm module "heading" ReDoS



This module exploits a Regular Expression Denial of Service vulnerability in the npm module "marked". The vulnerable portion of code that this module targets is in the "heading" regular expression. Web applications that use "marked" for generating html from markdown are vulnerable. Versions up to 0.4.0 are vulnerable.


  • Adam Cazzolla, Sonatype Security Research
  • Nick Starke, Sonatype Security Research


Module Options

To display the available options, load the module within the Metasploit console and run the commands 'show options' or 'show advanced':

msf > use auxiliary/dos/http/marked_redos
msf auxiliary(marked_redos) > show actions
msf auxiliary(marked_redos) > set ACTION < action-name >
msf auxiliary(marked_redos) > show options
    ...show and set options...
msf auxiliary(marked_redos) > run 

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