Vulnerabilities > CVE-2023-46725 - Time-of-check Time-of-use (TOCTOU) Race Condition vulnerability in Foodcoopshop
Summary
FoodCoopShop is open source software for food coops and local shops. Versions starting with 3.2.0 prior to 3.6.1 are vulnerable to server-side request forgery. In the Network module, a manufacturer account can use the `/api/updateProducts.json` endpoint to make the server send a request to an arbitrary host. This means that the server can be used as a proxy into the internal network where the server is. Furthermore, the checks on a valid image are not adequate, leading to a time of check time of use issue. For example, by using a custom server that returns 200 on HEAD requests, then return a valid image on first GET request and then a 302 redirect to final target on second GET request, the server will copy whatever file is at the redirect destination, making this a full SSRF. Version 3.6.1 fixes this vulnerability.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Leveraging Race Conditions via Symbolic Links This attack leverages the use of symbolic links (Symlinks) in order to write to sensitive files. An attacker can create a Symlink link to a target file not otherwise accessible to her. When the privileged program tries to create a temporary file with the same name as the Symlink link, it will actually write to the target file pointed to by the attackers' Symlink link. If the attacker can insert malicious content in the temporary file she will be writing to the sensitive file by using the Symlink. The race occurs because the system checks if the temporary file exists, then creates the file. The attacker would typically create the Symlink during the interval between the check and the creation of the temporary file.
- Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions This attack targets a race condition occurring between the time of check (state) for a resource and the time of use of a resource. The typical example is the file access. The attacker can leverage a file access race condition by "running the race", meaning that he would modify the resource between the first time the target program accesses the file and the time the target program uses the file. During that period of time, the attacker could do something such as replace the file and cause an escalation of privilege.