Hackers have been scanning the Internet for Oracle WebLogic Server installations that can be taken over using a recently addressed vulnerability. While patched systems should be protected against attacks, experts claim the fix implemented by Oracle can be bypassed.
One of the 254 issues resolved by Oracle with its April 2018 CPU is CVE-2018-2628, a critical remote command execution flaw affecting versions 10.3.6.0, 18.104.22.168, 22.214.171.124 and 126.96.36.199 of the Oracle WebLogic Server (Fusion Middleware) Java EE application server. Oracle has credited Liao Xinxi of the NSFOCUS Security Team and an individual who uses the online moniker loopx9 for reporting this security hole to the company.
Unauthenticated attackers can exploit this vulnerability remotely via the T3 transport protocol on TCP port 7001 and the task is made easy by the fact that proof-of-concept (PoC) code has already been made available.
One of the first people to disclose details of the vulnerability was Liao Xinxi himself. Developer Davide Tampellini used that information along with PoC code released by others to create a weaponized exploit that can be used to spawn a remote shell.
GreyNoise Intelligence reported seeing a “large spike” in devices scanning the Web for port 7001 shortly after the first PoCs surfaced. GreyNoise’s reports are backed by data from other companies, including SANS and Qihoo 360.
While there have not been any reports of servers actually being hacked using CVE-2018-2628, Oracle WebLogic Server has been known to be targeted by malicious actors. For instance, FireEye revealed in February that cybercriminals had been exploiting CVE-2017-10271, a WebLogic Server flaw patched by Oracle in October 2017, to deliver cryptocurrency miners. A possibly related threat group was also spotted recently exploiting the Drupal vulnerability known as Drupalgeddon2.
While users should in theory be protected against attacks exploiting CVE-2018-2628 if they have applied Oracle’s patch, a China-based security researcher who uses the online moniker Pyn3rd claims the fix can be easily bypassed.
Researcher Kevin Beaumont confirmed that bypassing the patch is possible and advised users to block port 7001 to mitigate attacks.
SecurityWeek has reached out to Oracle for comment and will update this article if the company responds.