Find, fix and prevent vulnerabilities in your code.

Overview

Affected versions of this package are vulnerable to Directory Traversal via unsanitized input in the prefix, postfix, or dir parameters during path construction. An attacker can create files outside the intended temporary directory, potentially overwriting or placing files in sensitive locations, by supplying crafted values containing traversal sequences or absolute paths.

Details

A Directory Traversal attack (also known as path traversal) aims to access files and directories that are stored outside the intended folder. By manipulating files with "dot-dot-slash (../)" sequences and its variations, or by using absolute file paths, it may be possible to access arbitrary files and directories stored on file system, including application source code, configuration, and other critical system files.

Directory Traversal vulnerabilities can be generally divided into two types:

• Information Disclosure: Allows the attacker to gain information about the folder structure or read the contents of sensitive files on the system.

st is a module for serving static files on web pages, and contains a vulnerability of this type. In our example, we will serve files from the public route.

If an attacker requests the following URL from our server, it will in turn leak the sensitive private key of the root user.

curl http://localhost:8080/public/%2e%2e/%2e%2e/%2e%2e/%2e%2e/%2e%2e/root/.ssh/id_rsa

Note %2e is the URL encoded version of . (dot).

• Writing arbitrary files: Allows the attacker to create or replace existing files. This type of vulnerability is also known as Zip-Slip.

One way to achieve this is by using a malicious zip archive that holds path traversal filenames. When each filename in the zip archive gets concatenated to the target extraction folder, without validation, the final path ends up outside of the target folder. If an executable or a configuration file is overwritten with a file containing malicious code, the problem can turn into an arbitrary code execution issue quite easily.

The following is an example of a zip archive with one benign file and one malicious file. Extracting the malicious file will result in traversing out of the target folder, ending up in /root/.ssh/ overwriting the authorized_keys file:

2018-04-15 22:04:29 .....           19           19  good.txt
2018-04-15 22:04:42 .....           20           20  ../../../../../../root/.ssh/authorized_keys

Remediation

Upgrade tmp to version 0.2.6 or higher.

References

• GitHub Advisory
• GitHub Commit

Overview

ip is a Node library.

Affected versions of this package are vulnerable to Server-side Request Forgery (SSRF) via the ip.isPublic() and ip.isPrivate() functions. An attacker can interact with internal network resources by supplying specially crafted IP address such as octal localhost format ("017700000001") that is incorrectly identified as public.

Note:

This issue exists because of an incomplete fix for CVE-2024-29415.

PoC

Test octal localhost bypass:

node -e "const ip=require('ip'); console.log('017700000001 bypass:', ip.isPublic('017700000001'));" - returns true

Remediation

There is no fixed version for ip.

References

• GitHub Issue
• Security Report

Overview

ip is a Node library.

Affected versions of this package are vulnerable to Server-side Request Forgery (SSRF) via the ip.isPublic() and ip.isPrivate() functions. An attacker can interact with internal network resources by supplying specially crafted IP address such as null route ("0") that is being incorrectly identified as public.

Note: This issue exists because of an incomplete fix for CVE-2024-29415.

Exploit is only possible if the application and operating system interpret connection attempts to 0 or 0.0.0.0 as connections to 127.0.0.1.

PoC

Test null route bypass:

node -e "const ip=require('ip'); console.log('0 bypass:', ip.isPublic('0'));" - returns true

Remediation

There is no fixed version for ip.

References

• GitHub Issue
• Security Report