Tenable Research Advisory: Advantech WebAccess Remote Command Execution Still Exploitable
Tenable Researcher Chris Lyne discovered that Advantech WebAccess versions 8.3, 8.3.1 and 8.3.2 are still vulnerable to remote command execution CVE-2017-16720, which was originally disclosed by ZDI in January 2018 and has a public exploit.
Background
Tenable Research’s Chris Lyne has discovered that Advantech WebAccess remains unprotected against a public exploit several months after a patch was released. Vulnerable WebAccess instances remain susceptible to an unauthenticated remote code execution (RCE) attack (CVE-2017-16720). WebAccess versions 8.3, 8.3.1 and 8.3.2 are affected.
On January 4, 2018, ICS-CERT released ICSA-18-004-02A to detail several vulnerabilities reported for Advantech WebAccess. One of the vulnerabilities, CVE-2017-16720, which was also disclosed by the Zero Day Initiative (ZDI), allows an unauthenticated remote attacker to execute arbitrary system commands.
The mitigation section of the ICS-CERT advisory states, “Advantech has released WebAccess Version 8.3 to address the reported vulnerabilities.” In March, two months after the release of the ICS-CERT advisory, a public exploit leveraging CVE-2017-16720 was published to the Exploit Database.
Vulnerability details
This vulnerability allows for remote command execution via the Remote Procedure Call (RPC) protocol over TCP port 4592. By utilizing malicious Distributed Computing Environment / Remote Procedure Calls (DCERPC), the webvrpcs.exe service will pass command line instructions to the host.
The webvrpcs.exe service runs with administrator access rights, which means an attacker can take control of an asset at that privilege level.
Exploitation
There is a publicly available Proof of Concept (PoC) for this vulnerability. Little additional research would be required for an attacker to utilize this PoC against any WebAccess target.
Since this vulnerability was not previously patched, and a public exploit has been available for quite some time, up-to-date assets running WebAccess could have been exploited.
Vendor response
ICS-CERT indicates Advantech has a fix that will be released in September. We will update this section as we get more information, and remediation information becomes available.
Identifying Affected Systems
Tenable has the following plugin available for identifying vulnerable assets.
|
Plugin ID |
Description |
|
Advantech WebAccess/SCADA Network Service Detection |
Learn more:
- Visit the Tenable Techblog on Medium to read researcher Chris Lyne's in-depth story about his work uncovering this vulnerability.
- Visit the Tenable Research Advisories page to stay up-to-date on security vulnerabilities in third-party software discovered by a dedicated team supported by researchers and engineers at Tenable.
Learn more about Tenable.io, the first Cyber Exposure platform for holistic management of your modern attack surface. Get a free 60-day trial of Tenable.io Vulnerability Management.
Related Articles
Volt Typhoon: U.S. Critical Infrastructure Targeted by State-Sponsored Actors
November 19, 2024Volt Typhoon, a state-sponsored actor linked to the People’s Republic of China, has consistently targeted U.S. critical infrastructure with the intent to maintain persistent access. Tenable Research examines the tactics, techniques and procedures of this threat actor.
CVE-2024-0012, CVE-2024-9474: Zero-Day Vulnerabilities in Palo Alto PAN-OS Exploited In The Wild
November 18, 2024Palo Alto Networks confirmed two zero-day vulnerabilities were exploited as part of attacks in the wild against PAN-OS devices, with one being attributed to Operation Lunar Peek.
Microsoft’s November 2024 Patch Tuesday Addresses 87 CVEs (CVE-2024-43451, CVE-2024-49039)
November 12, 2024Microsoft addresses 87 CVEs and one advisory (ADV240001) in its November 2024 Patch Tuesday release, with four critical vulnerabilities and four zero-day vulnerabilities, including two that were exploited in the wild.
Volt Typhoon: What State and Local Government Officials Need to Know
November 19, 2024Increased activity from the state-sponsored threat group Volt Typhoon raises concerns about the cybersecurity of U.S. critical infrastructure. Here’s how you can identify potential exposures and attack paths.
Volt Typhoon: U.S. Critical Infrastructure Targeted by State-Sponsored Actors
November 19, 2024Volt Typhoon, a state-sponsored actor linked to the People’s Republic of China, has consistently targeted U.S. critical infrastructure with the intent to maintain persistent access. Tenable Research examines the tactics, techniques and procedures of this threat actor.
CVE-2024-0012, CVE-2024-9474: Zero-Day Vulnerabilities in Palo Alto PAN-OS Exploited In The Wild
November 18, 2024Palo Alto Networks confirmed two zero-day vulnerabilities were exploited as part of attacks in the wild against PAN-OS devices, with one being attributed to Operation Lunar Peek.
- Vulnerability Management