ISC Stormcast Update: Honeypot Automation and SIEM Logging Challenges

The SANS Internet Storm Center (ISC) Stormcast for April 23, 2025, highlights ongoing challenges in honeypot maintenance and SIEM logging, with technical insights into dynamic IP management and Elasticsearch compatibility issues. This update is particularly relevant for security teams managing infrastructure visibility and threat detection pipelines.

TL;DR: Key Takeaways for CISOs

Honeypot IP Management: Dynamic IPs complicate remote access; scripting solutions using AWS Route 53 are now deployed.
SIEM Logging Disruptions: Filebeat version mismatches (8.15.1 vs. 8.17.3) caused gaps in Zeek log forwarding to Elasticsearch.
Emerging Threats: APT29 phishing campaigns targeting healthcare, per CISA Alert TA24-100A.

Honeypot Automation with Dynamic DNS

Jesse La Grew’s ISC diary entry details the challenges of maintaining honeypots with dynamic public IPs. The solution involves scripting iptables updates via DNS resolution, leveraging AWS Route 53 for real-time IP mapping. A Bash script inserts rules into /etc/network/iptables to whitelist administrative ports dynamically:

sed -i "/START: allow access to admin ports for local IPs/a -A INPUT -i $interface -s $remoteip -p tcp --dport 12222 -j ACCEPT" /etc/network/iptables

This approach reduces manual intervention and is compatible with pfSense firewalls. The DShield-SIEM GitHub repository provides additional context on integrating these scripts with SIEM logging pipelines.

SIEM Logging: Filebeat and Elasticsearch Compatibility

Version mismatches between Filebeat (8.15.1) and Elasticsearch (8.17.3) disrupted Zeek log ingestion in ELK stacks. The fix requires aligning versions and updating Filebeat configurations:

filebeat.inputs:
  - type: log
    paths: ["/var/log/zeek/*.log"]

Organizations using Zeek for network monitoring should validate log forwarding paths and version dependencies. The ISC diary notes that unpatched systems may miss critical threat indicators, such as IoT botnet activity observed on April 9, 2025.

Threat Intelligence: APT29 and DKIM Replay Attacks

The April 2, 2025 Stormcast episode warns of DKIM replay attacks exploiting weak email authentication. SSL.com has released patches, but unpatched systems remain vulnerable. APT29’s recent phishing campaigns, documented in CISA Alert TA24-100A, emphasize the need for network segmentation and MFA in healthcare environments.

Relevance and Remediation

For threat hunters, the iptables scripting method provides a template for automating infrastructure updates. Blue teams should prioritize Elasticsearch version audits and monitor Zeek log paths. The SANS “Introduction to Malware Binary Triage” course (Coupon: MWNEWS10) offers further training on related techniques.

Future ISC updates may address VPN gateway exploits, as seen in the April 21, 2025 episode. Proactive patching and DNS-based automation remain critical for maintaining defensive postures.