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Discussion on: Regex 101

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valeriavg profile image
Valeria

One should be aware of Regular Expression Denial of Service attack when validating user input on the backend.
These seemingly simple regular expressions can cause infinite loops:

(a+)+
([a-zA-Z]+)*
(a|aa)+
(a|a?)+
(.*a){x} for x \> 10
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shreyazz profile image
Shreyas Pahune Author

Thanks for the info 😇