make issue comment unreadable by using 
HackerOne report #860559 by tiradorngpilipinas
on 2020-04-27, assigned to @jeremymatos:
Summary
Hi gitlab team. I find out that when creating an issue and then commenting an %00 . The attacker can make the commend issue unusable just by one comment. The attacker need only 1 comment and comment in the issue will not read anymore
Steps to reproduce
(Step-by-step guide to reproduce the issue, including:)
- go to gitlab.com and create an project
- in project create an issue
- comment 5 comments for content of comments
- input attacker comment
- Now all 5 comments will not readable and it will say Something went wrong while fetching comments. Please try again.
Impact
making comment not readable and unusable just by using %00
Attachments
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