CVE-2026-22885 Overview
CVE-2026-22885 is a memory leak vulnerability affecting EnOcean SmartServer IoT version 4.60.009 and prior. The flaw resides in the handling of LON IP-852 management messages. Remote attackers can send specially crafted IP-852 messages to trigger a memory leak from the program's memory. The weakness is classified under [CWE-125] (Out-of-bounds Read), which allows unauthorized reading of process memory contents.
The vulnerability does not require authentication or user interaction, but attack complexity is high. Successful exploitation results in confidentiality impact through unintended memory disclosure. CISA published advisory ICSA-26-050-01 covering this issue within industrial control system environments.
Critical Impact
Remote attackers can leak portions of process memory from EnOcean SmartServer IoT devices by transmitting malformed LON IP-852 management messages, potentially exposing sensitive operational data.
Affected Products
- EnOcean SmartServer IoT version 4.60.009
- EnOcean SmartServer IoT versions prior to 4.60.009
- LON IP-852 management message handler component
Discovery Timeline
- 2026-02-20 - CVE-2026-22885 published to NVD
- 2026-04-15 - Last updated in NVD database
Technical Details for CVE-2026-22885
Vulnerability Analysis
The vulnerability exists in the LON IP-852 management message processing logic of the EnOcean SmartServer IoT. LON IP-852 is the tunneling protocol used to transport ANSI/CEA-709.1 LonTalk control network traffic over IP. The SmartServer acts as a gateway between LON networks and IP-based management systems.
When the server parses crafted IP-852 management messages, it reads beyond the intended buffer boundary. This out-of-bounds read returns adjacent process memory to the requester. Repeated requests progressively leak data from the program's address space.
The weakness aligns with [CWE-125] (Out-of-bounds Read). Although the vulnerability does not affect integrity or availability, leaked memory may contain configuration data, internal pointers, or fragments of control messages relevant to adjacent industrial systems.
Root Cause
The root cause is insufficient bounds checking on incoming IP-852 management message fields. The parser trusts length or offset values supplied in the protocol header without validating them against the actual received payload size. This permits the read operation to extend past the message buffer.
Attack Vector
An attacker reaches the vulnerable code path over the network by sending IP-852 packets to the SmartServer's management interface. Authentication is not required. However, the high attack complexity reflects the need for specific protocol knowledge and likely network adjacency to industrial deployments where IP-852 traffic is permitted. The attacker crafts management messages with manipulated length or offset fields, then collects the responses to harvest leaked memory.
No verified public exploit code is available. The vulnerability mechanism is described in the CISA ICS Advisory ICSA-26-050-01 and the GitHub CSAF White Paper.
Detection Methods for CVE-2026-22885
Indicators of Compromise
- Unusual volumes of inbound IP-852 management traffic on UDP port 1628 directed at SmartServer IoT devices
- Malformed LON IP-852 packets with inconsistent header length fields versus actual payload size
- Repeated identical or near-identical management message requests from a single source within short time windows
Detection Strategies
- Deploy network intrusion detection signatures that validate IP-852 message length fields against received packet size
- Inspect SmartServer IoT logs for repeated management message processing errors or anomalous parsing events
- Baseline normal IP-852 traffic patterns between management stations and SmartServer endpoints, then alert on deviations
Monitoring Recommendations
- Forward SmartServer IoT system logs to a centralized SIEM for correlation with network telemetry
- Monitor egress from SmartServer devices for unexpected data flows that could indicate exfiltration of leaked memory contents
- Track firmware versions across the fleet and alert on devices still running 4.60.009 or earlier
How to Mitigate CVE-2026-22885
Immediate Actions Required
- Upgrade EnOcean SmartServer IoT to the current stable release listed in the EnOcean Wiki Release Notes
- Restrict network access to the IP-852 management interface using firewall rules and segmentation
- Inventory all SmartServer IoT deployments and identify devices running 4.60.009 or prior
Patch Information
EnOcean addresses this issue in releases after 4.60.009. Refer to the EnOcean Wiki Release Notes for the current stable build and apply the update following the vendor's documented procedure. Additional hardening guidance is provided in the EnOcean Wiki Security Enhancements documentation.
Workarounds
- Place SmartServer IoT devices behind a firewall that blocks unsolicited IP-852 traffic from untrusted networks
- Limit IP-852 management communication to known, trusted management station IP addresses through allow-listing
- Disable the LON IP-852 interface on devices that do not require remote LON-over-IP connectivity
# Configuration example: restrict IP-852 (UDP/1628) to trusted management hosts
iptables -A INPUT -p udp --dport 1628 -s 10.10.5.10 -j ACCEPT
iptables -A INPUT -p udp --dport 1628 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
