Cybersecurity researchers have developed a proof-of-concept (PoC) code that exploits a recently disclosed critical flaw in the Apache OfBiz open-source Enterprise Resource Planning (ERP) system to execute a memory-resident payload.

The vulnerability in question is CVE-2023-51467 (CVSS score: 9.8), a bypass for another severe shortcoming in the same software (CVE-2023-49070, CVSS score: 9.8) that could be weaponized to circumvent authentication and remotely execute arbitrary code.

While it was fixed in Apache OFbiz version 18.12.11 released last month, threat actors have been observed attempting to exploit the flaw, targeting vulnerable instances.

The latest findings from VulnCheck show that CVE-2023-51467 can be exploited to execute a payload directly from memory, leaving little to no traces of malicious activity.

Security flaws disclosed in Apache OFBiz (e.g., CVE-2020-9496) have been exploited by threat actors in the past, including by threat actors associated with the Sysrv botnet. Another three-year-old bug in the software (CVE-2021-29200) has witnessed exploitation attempts from 29 unique IP addresses over the past 30 days, per data from GreyNoise.

What’s more, Apache OFBiz was also one of the first products to have a public exploit for Log4Shell (CVE-2021-44228), illustrating that it continues to be of interest to both defenders and attackers alike.

CVE-2023-51467 is no exception, with details about a remote code execution endpoint (“/webtools/control/ProgramExport”) as well as PoC for command execution emerging merely days after public disclosure.

While security guardrails (i.e., Groovy sandbox) have been erected such that they block any attempts to upload arbitrary web shells or run Java code via the endpoint, the incomplete nature of the sandbox means that an attacker could run curl commands and obtain a bash reverse shell on Linux systems.

“For an advanced attacker, though, these payloads aren’t ideal,” VulnCheck’s Chief Technology Officer Jacob Baines said. “They touch the disk and rely on Linux-specific behavior.”

The Go-based exploit devised by VulnCheck is a cross-platform solution that works on both Windows and Linux as well as gets around the denylist by taking advantage of groovy.util.Eval functions to launch an in-memory Nashorn reverse shell as the payload.

“OFBiz is not widely popular, but it has been exploited in the past. There is a fair deal of hype around CVE-2023-51467 but no public weaponized payload, which called into question if it was even possible,” Baines said. “We’ve concluded that not only is it possible, but we can achieve arbitrary in memory code execution.”