Is CVE-2017-17671 actively exploited?

No active exploitation of CVE-2017-17671 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2017-17671 be exploited remotely?

Yes. CVE-2017-17671 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2017-17671?

CVE-2017-17671 has a CVSS score of 9.8 (CRITICAL).

HOME VULNERABILITIESCVE-2017-17671

CRITICAL

CVE-2017-17671

CWE-22Published: December 14, 2017· Updated: Jun 17, 2026

9.8

CVSS v3.1

Official Description

vBulletin through 5.3.x on Windows allows remote PHP code execution because a require_once 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.

NVD Source

Technical Analysis

CVE-2017-17671 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 9.8.