cybersecurityvbulletinrcepatch managementsmall and medium businesses
vBulletin fixes critical pre-auth RCE flaw with public exploit
July 28, 2026
Back to all postsA critical Remote Code Execution (RCE) vulnerability has been identified in the popular open-source forum software, vBulletin. The flaw, tracked as CVE-2021-34658, allows an attacker to execute arbitrary code without requiring authentication. This vulnerability can be exploited by malicious actors to gain unauthorized access to vulnerable systems and potentially cause significant damage, such as data theft or system takeover. Given the widespread use of vBulletin in Canada, this issue poses a significant threat to small and medium-sized businesses (SMBs) that utilize the software for their online communities or forums. To mitigate the risk, it is strongly recommended that all vBulletin users promptly install the latest available patch (version 5.6.4) to protect their systems from potential attacks.
Source: BleepingComputer
cybersecurityvbulletinrcepatch managementsmall and medium businesses
Concerned about this threat to your business?
We help Canadian SMBs deploy the controls discussed in this article. Free 30-minute assessment — no obligation.