CVE-2017-17671: Path Traversal
vBulletin through 5.3.x on Windows allows remote PHP code execution because a requireonce call is reachable with an unauthenticated request that can include directory traversal sequences to specify an arbitrary pathname, and because ../ traversal is blocked but ..\ traversal is not blocked. For example, an attacker can make an invalid HTTP request containing PHP code, and then make an index.php?routestring= request with enough instances of ".." to reach an Apache HTTP Server log file.
Affected Software
Event History
Frequently Asked Questions
What is CVE-2017-17671?
CVE-2017-17671 is a vulnerability in vBulletin through 5.3.x on Windows that allows remote PHP code execution.
How does CVE-2017-17671 work?
CVE-2017-17671 can be exploited by sending an unauthenticated request with directory traversal sequences to specify an arbitrary pathname, leading to remote PHP code execution.
What is the severity of CVE-2017-17671?
CVE-2017-17671 has a severity rating of 9.8 (critical).
Which versions of vBulletin are affected by CVE-2017-17671?
vBulletin versions 5.0.1 to 5.3.3 are affected by CVE-2017-17671.
How can I fix CVE-2017-17671?
To fix CVE-2017-17671, you should upgrade to a patched version of vBulletin.