There is no way to call readLine() safely since it is, by its nature, a read that must be terminated by the stream provider. Furthermore, a stream of data provided by an untrusted source could lead to a denial of service attack, as attackers can provide an infinite stream of bytes until the process runs out of memory.
Fixing it is straightforward using an API which limits the amount of expected characters to some sane limit. This is what our changes look like:
+ import io.github.pixee.security.BoundedLineReader;
...
BufferedReader reader = getReader();
- String line = reader.readLine(); // unlimited read, can lead to DoS
+ String line = BoundedLineReader.readLine(reader, 5_000_000); // limited to 5MB
More reading
* [https://vulncat.fortify.com/en/detail?id=desc.dataflow.abap.denial_of_service](https://vulncat.fortify.com/en/detail?id=desc.dataflow.abap.denial_of_service)
* [https://cwe.mitre.org/data/definitions/400.html](https://cwe.mitre.org/data/definitions/400.html)
I have additional improvements ready for this repo! If you want to see them, leave the comment:
This change hardens all
BufferedReader#readLine()operations against memory exhaustion.There is no way to call
readLine()safely since it is, by its nature, a read that must be terminated by the stream provider. Furthermore, a stream of data provided by an untrusted source could lead to a denial of service attack, as attackers can provide an infinite stream of bytes until the process runs out of memory.Fixing it is straightforward using an API which limits the amount of expected characters to some sane limit. This is what our changes look like:
More reading
* [https://vulncat.fortify.com/en/detail?id=desc.dataflow.abap.denial_of_service](https://vulncat.fortify.com/en/detail?id=desc.dataflow.abap.denial_of_service) * [https://cwe.mitre.org/data/definitions/400.html](https://cwe.mitre.org/data/definitions/400.html)I have additional improvements ready for this repo! If you want to see them, leave the comment:
... and I will open a new PR right away!
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