Version Details and Security Vulnerabilities

libxmljs2 is vulnerable to a type confusion vulnerability when parsing a specially crafted XML while invoking the namespaces() function (which invokes XmlNode::get_local_namespaces()) on a grand-child of a node that refers to an entity. This vulnerability can lead to denial of service and remote code execution.

libxmljs2 is vulnerable to type confusion when parsing a specially crafted XML while invoking a function on the result of attrs() that was called on a parsed node. This vulnerability might lead to denial of service (on both 32-bit systems and 64-bit systems), data leak, infinite loop and remote code execution (on 32-bit systems with the XML_PARSE_HUGE flag enabled). At the time of publication, there is no fix.

Description:

During some analysis today on npm's node-tar package I came across the folder creation process, Basicly if you provide node-tar with a path like this ./a/b/c/foo.txt it would create every folder and sub-folder here a, b and c until it reaches the last folder to create foo.txt, In-this case I noticed that there's no validation at all on the amount of folders being created, that said we're actually able to CPU and memory consume the system running node-tar and even crash the nodejs client within few seconds of running it using a path with too many sub-folders inside

Steps To Reproduce:

You can reproduce this issue by downloading the tar file I provided in the resources and using node-tar to extract it, you should get the same behavior as the video

Proof Of Concept:

Here's a video show-casing the exploit:

Impact

Denial of service by crashing the nodejs client when attempting to parse a tar archive, make it run out of heap memory and consuming server CPU and memory resources

Report resources

payload.txt archeive.tar.gz

Note

This report was originally reported to GitHub bug bounty program, they asked me to report it to you a month ago