PHOENIX CONTACT mGuard Improper Validation of Integrity Check Value (CVE-2018-5441)

# ICS Advisory (ICSA-18-030-01) ## PHOENIX CONTACT mGuard Original release date: January 30, 2018 [Print Document](javascript:window.print\(\);) [Tweet](https://twitter.com/share?url=https%3A%2F%2Fus- cert.cisa.gov%2Fics%2Fadvisories%2FICSA-18-030-01) [Like Me](https://www.facebook.com/sharer.php?u=https%3A%2F%2Fus- cert.cisa.gov%2Fics%2Fadvisories%2FICSA-18-030-01) [Share](http://www.addthis.com/bookmark.php?url=https%3A%2F%2Fus- cert.cisa.gov%2Fics%2Fadvisories%2FICSA-18-030-01) ### Legal Notice All information products included in [https://us-cert.gov/ics](/ics) are provided "as is" for informational purposes only. The Department of Homeland Security (DHS) does not provide any warranties of any kind regarding any information contained within. DHS does not endorse any commercial product or service, referenced in this product or otherwise. Further dissemination of this product is governed by the Traffic Light Protocol (TLP) marking in the header. For more information about TLP, see [https://www.us- cert.gov/tlp/](/tlp/). * * * ### **CVSS v3 7.8** **ATTENTION:** Low skill level to exploit. **Vendor:** PHOENIX CONTACT **Equipment:** mGuard **Vulnerability:** Improper Validation of Integrity Check Value ## AFFECTED PRODUCTS The following versions of mGuard, a network device, are affected: * mGuard firmware versions 7.2 to 8.6.0 ## IMPACT Successful exploitation of this vulnerability could allow for an attacker to modify firmware update packages. ## MITIGATION PHOENIX CONTACT recommends that affected users upgrade to firmware version 8.6.1 * MGUARD CENTERPORT <http://www.phoenixcontact.net/qr/2702547/firmware_update> * MGUARD DELTA TX/TX <http://www.phoenixcontact.net/qr/2700967/firmware_update> * MGUARD DELTA TX/TX VPN <http://www.phoenixcontact.net/qr/2700968/firmware_update> * MGUARD GT/GT <http://www.phoenixcontact.net/qr/2700197/firmware_update> * MGUARD GT/GT VPN <http://www.phoenixcontact.net/qr/2700198/firmware_update> * MGUARD PCI4000 VPN <http://www.phoenixcontact.net/qr/2701275/firmware_update> * MGUARD PCIE4000 VPN <http://www.phoenixcontact.net/qr/2701278/firmware_update> * MGUARD RS2000 TX/TX VPN <http://www.phoenixcontact.net/qr/2700642/firmware_update> * MGUARD RS2000 TX/TX-B <http://www.phoenixcontact.net/qr/2702139/firmware_update> * MGUARD RS2005 TX VPN <http://www.phoenixcontact.net/qr/2701875/firmware_update> * MGUARD RS4000 TX/TX <http://www.phoenixcontact.net/qr/2700634/firmware_update> * MGUARD RS4000 TX/TX VPN <http://www.phoenixcontact.net/qr/2200515/firmware_update> * MGUARD RS4000 TX/TX VPN-M <http://www.phoenixcontact.net/qr/2702465/firmware_update> * MGUARD RS4000 TX/TX-P <http://www.phoenixcontact.net/qr/2702259/firmware_update> * MGUARD RS4004 TX/DTX <http://www.phoenixcontact.net/qr/2701876/firmware_update> * MGUARD RS4004 TX/DTX VPN <http://www.phoenixcontact.net/qr/2701877/firmware_update> * MGUARD SMART2 <http://www.phoenixcontact.net/qr/2700640/firmware_update> * MGUARD SMART2 VPN <http://www.phoenixcontact.net/qr/2700639/firmware_update> * MGUARD RS2000 3G VPN <http://www.phoenixcontact.net/qr/2903441/firmware_update> * MGUARD RS4000 3G VPN <http://www.phoenixcontact.net/qr/2903440/firmware_update> * MGUARD CORE TX VPN [http://www.phoenixcontact.net/qr/2700640/firmware_update](http://www.phoenixcontact.net/qr/2700640/firmware_update%20) * MGUARD RS2000 4G VPN <http://www.phoenixcontact.net/qr/2903588/firmware_update> * MGUARD RS4000 4G VPN <http://www.phoenixcontact.net/qr/2903586/firmware_update> NCCIC recommends users take defensive measures to minimize the risk of exploitation of these vulnerabilities. Specifically, users should: * Minimize network exposure for all control system devices and/or systems, and ensure that they are [not accessible from the Internet](/ics/alerts/ICS-ALERT-10-301-01). * Locate control system networks and remote devices behind firewalls, and isolate them from the business network. * When remote access is required, use secure methods, such as Virtual Private Networks (VPNs), recognizing that VPNs may have vulnerabilities and should be updated to the most current version available. Also recognize that VPN is only as secure as the connected devices. NCCIC reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures. NCCIC also provides a section for [control systems security recommended practices](/ics/content/recommended-practices) on the ICS-CERT web page. Several recommended practices are available for reading and download, including [Improving Industrial Control Systems Cybersecurity with Defense-in- Depth Strategies.](/sites/default/files/recommended_practices/NCCIC_ICS- CERT_Defense_in_Depth_2016_S508C.pdf) Additional mitigation guidance and recommended practices are publicly available in the NCCIC Technical Information Paper, [ICS-TIP-12-146-01B-- Targeted Cyber Intrusion Detection and Mitigation Strategies](/ics/tips/ICS- TIP-12-146-01B), that is available for download from the [ICS-CERT web site](/ics/). Organizations observing any suspected malicious activity should follow their established internal procedures and report their findings to NCCIC for tracking and correlation against other incidents. No known public exploits specifically target this vulnerability. This vulnerability is not remotely exploitable. ## VULNERABILITY OVERVIEW ## [IMPROPER VALIDATION OF INTEGRITY CHECK VALUE CWE-354](https://cwe.mitre.org/data/definitions/354.html) mGuard devices rely on internal checksums for verification of the internal integrity of the update packages. Verification may not always be performed correctly, allowing an attacker to modify firmware update packages. [CVE-2018-5441](http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2018-5441) has been assigned to this vulnerability. A CVSS v3 base score of 7.8 has been assigned; the CVSS vector string is ([AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H](https://www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H)). ## RESEARCHER PHOENIX CONTACT reported to CERT@VDE that their products are affected. CERT@VDE coordinated this vulnerability with NCCIC. ## BACKGROUND **Critical Infrastructure Sectors:** Communications, Critical Manufacturing, Information Technology **Countries/Areas Deployed:** Worldwide **Company Headquarters Location:** Germany