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PatchSiren cyber security CVE debrief

CVE-2024-7755 HMS Networks CVE debrief

The HMS Networks EWON FLEXY 202 industrial gateway transmits credentials using Base64 encoding without encryption, enabling network-level attackers to capture and decode authentication material via passive traffic analysis. Published 2024-10-17, this HIGH severity vulnerability (CVSS 8.2) affects Firmware version 14.2s0. The attack requires no privileges and low attack complexity, with network access and user interaction as prerequisites. The confidentiality impact is rated HIGH, with LOW integrity impact. HMS Networks has released firmware version 14.9s2 to address this weakness. Organizations should prioritize updating affected devices and implementing network segmentation controls to limit credential exposure.

Vendor
HMS Networks
Product
EWON FLEXY 202
CVSS
HIGH 8.2
CISA KEV
Not listed in stored evidence
Original CVE published
2024-10-17
Original CVE updated
2024-10-17
Advisory published
2024-10-17
Advisory updated
2024-10-17

Who should care

Organizations operating HMS Networks EWON FLEXY 202 industrial gateways in manufacturing, energy, water/wastewater, and other OT environments. Security teams responsible for industrial network segmentation and credential protection. Compliance officers managing IEC 62443 or NIST CSF alignment for industrial control systems.

Technical summary

The EWON FLEXY 202 industrial gateway uses Base64 encoding—a reversible encoding scheme, not encryption—for credential transmission. Base64 provides no confidentiality protection; encoded credentials decode trivially with standard tools. An attacker with network access can passively capture traffic containing authentication exchanges and recover plaintext credentials. The vulnerability exists in Firmware 14.2s0. The CVSS 3.1 vector (AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N) reflects network attack vector, low complexity, no privileges required, user interaction needed, scope change, high confidentiality impact, and low integrity impact. HMS Networks has addressed this in firmware 14.9s2.

Defensive priority

HIGH

Recommended defensive actions

  • Update EWON FLEXY 202 devices to firmware version 14.9s2 or later as recommended by HMS Networks
  • Implement network segmentation to isolate industrial control system devices from untrusted networks
  • Deploy encrypted management channels (VPN, TLS) for all remote access to affected devices
  • Monitor network traffic for unauthorized credential capture attempts on industrial segments
  • Review and rotate credentials that may have been exposed prior to patching
  • Apply CISA ICS recommended practices for defense-in-depth architecture
  • Validate that replacement firmware implements proper credential encryption rather than encoding

Evidence notes

CISA ICS advisory ICSA-24-291-04 confirms Base64 credential encoding in EWON FLEXY 202 Firmware 14.2s0. CVSS vector AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N sourced from official CISA CSAF document. Remediation guidance and firmware update path (14.9s2) provided by vendor through CISA-coordinated disclosure.

Official resources

2024-10-17