CVE-2017-17671
CriticalSummary
vBulletin versions up to 5.3.x on Windows allows remote PHP code execution due to the accessibility of a require_once call with an unauthenticated request that can include directory traversal sequences to specify an arbitrary pathname. The blocking of ../ traversal does not apply to ..\, allowing for exploitation of this vulnerability.
Risk Assessment
An attacker can exploit this vulnerability to execute malicious code on the server, potentially leading to system takeover or data leakage. Organizations should be aware of the risks associated with unauthorized access to system files.
Recommendation
It is recommended to update vBulletin to the latest version to eliminate this vulnerability. Additionally, implementing security mechanisms to prevent unauthorized file access and monitoring server logs for suspicious activities is advisable.
Other vulnerabilities in vBulletin
See all- CVE-2017-7569High
In vBulletin versions before 5.3.0, remote attackers can bypass the CVE-2016-6483 patch and conduct SSRF attacks by leveraging the behavior of the PHP parse_url function.
- CVE-2016-6483High
The media-file upload feature in vBulletin before certain versions allows remote attackers to conduct SSRF attacks via a crafted URL, resulting in a Redirection HTTP status code.
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vBulletin versions 5.x through 5.7.5 and 6.x through 6.2.1 contain an eval injection vulnerability in the vB5_Template_Runtime::runMaths() method, allowing unauthenticated remote attackers to execute arbitrary PHP code via crafted pagenav[pagenumber] parameter.
- CVE-2017-17672Critical
In vBulletin versions up to 5.3.x, there is an unauthenticated deserialization vulnerability that can lead to arbitrary file deletion and, under certain circumstances, code execution. This issue arises from the unsafe usage of PHP's unserialize() function in the cacheTemplates() method of the vB_Library_Template class, which is publicly exposed.
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A vulnerability in vBulletin 6.x in an unknown function of the Login component leads to cross-site scripting (XSS). The attack can be initiated remotely. The exploit has been made public.
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A vulnerability in vBulletin 3.8.7 allows a DoS attack via the misc.php?do=buddylist endpoint. An authenticated user with an excessively large buddy list can cause excessive memory consumption, exhausting system resources and crashing the forum.
Original NVD description (English source)
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.