SANS Stormcast Summary – March 6, 2025

Host: Johannes B. Ullrich
Main Topics: DShield Honeypot ELK Analysis; AMD CPU Jailbreak Vulnerability; VIM TAR Exploit; Snail Mail Ransomware Scam

Overview

Today’s episode covers recent advances and trending incidents in cybersecurity, including powerful data analysis options for DShield honeypots, a newly detailed severe AMD CPU vulnerability, a patch for a critical VIM editor exploit, and a surprising analog twist on ransomware with fake snail mail extortion attempts.

Key Discussion Points & Insights

1. DShield Honeypot & ELK Analysis Platform

Timestamp: 00:08–01:15

• DShield Honeypot Upgrade: Guy from the SANS Internet Stormcenter has enhanced the DShield honeypot’s capabilities by integrating a Kibana (ELK) interface, allowing more intuitive visualization and exploration of captured attack data.
  • “GUI has done an amazing job with our Deshield honeypot, allowing you to run a Kibana interface, all data being stored in elasticsearch and with that making the data that your honeypot collects much more approachable.” (Johannes B. Ullrich, 00:13)
• Data Overload?: There’s a “lot of data,” so Guy penned a diary/blog post to help users more effectively sift through events and spot attack patterns.
• Participation Encouraged: Running the DShield honeypot and sharing data benefits the broader security community, but note the ELK stack requires more processing power (“a little bit more powerful system than just sort of your basic Raspberry PI”).
• Actionable Takeaway: Consider deploying or upgrading your honeypot, and reference the blog for data management tips.

2. Jailbreaking AMD CPUs – Exposure and Patch

Timestamp: 01:16–03:09

• Critical Microcode Update Flaw: Google’s Bug Hunter team published exploit code and detailed analysis for a vulnerability (patched by AMD a month ago) that let attackers arbitrarily update the CPU’s microcode.
• Hashing Weakness: The underlying issue was a cryptographically weak hash function in AMD’s update mechanism, making it possible to inject malicious updates despite supposed signature protection.
• Potential Impact: The vulnerability could allow attackers to “jailbreak” the CPU—taking low-level control with unpredictable capabilities. The initial proof-of-concept demo forced the CPU’s random number generator to always return the same value, but new code enables substantially more.
  • “With the additional code released today and such, well really up to the attacker's creativity what they would like your CPU to do.” (Johannes B. Ullrich, 02:37)
• Patch Availability: Issue was addressed a month ago using a proprietary hash function; now it’s even more urgent to ensure all AMD CPUs are patched, as public exploit code is circulating.
• Verification: New details provide more ways for defenders to check if CPUs are patched.

3. VIM Editor Vulnerability: TAR Feature Code Execution

Timestamp: 03:10–04:17

• Functionality Gone Wrong: A recent feature in VIM allowed users to open and edit files within TAR archives. The vulnerability involved a failure to properly validate filenames, creating a code execution vector.
• Real-World Danger: Although user interaction is required (i.e., convincing someone to open a malicious TAR archive in VIM), sysadmins might trust VIM’s safety over other programs, making them susceptible.
  • “The sort of appearance of VIM being like simple and safe may make it actually easier to trick an administrator to open a file in VIM than it is to open a file like Invert or Acrobat Reader...” (Johannes B. Ullrich, 04:04)
• Recommendation: Apply the latest VIM update to mitigate this risk.

4. Snail Mail Ransomware Scam

Timestamp: 04:18–05:18

• Twist on Ransomware: GuidePoint Security discovered a campaign in which threat actors send real, physical letters (snail mail) to company executives. These letters claim to be from the BianLian ransomware group and threaten to leak stolen data unless ransom is paid.
• Likely a Hoax: Most of these threats are baseless—there’s no evidence of data theft; this is a scare tactic targeting non-technical execs who might bypass security vetting.
  • “At least as I said my take on it. No idea how successful this campaign is. And again, the letters are probably not related to the actual Pyongyang ransomware group. They're just some copycats that attempt sort of a new twist on this scare...” (Johannes B. Ullrich, 04:58)
• Contextual Outcome: Similar fake extortion attempts (via email) have previously duped up to 30% of recipients into paying.
  • “Sadly, these fake ransomware notes have been somewhat successful... thirty percent of the recipients... have actually paid up.” (Johannes B. Ullrich, 05:10)

Memorable Quotes & Moments

• “You may need a little bit more powerful system than just sort of your basic Raspberry PI in order to run all of this.” (Johannes B. Ullrich, 00:50)
• “The sort of appearance of VIM being like simple and safe may make it actually easier to trick an administrator to open a file in VIM than it is to open a file like Invert or Acrobat Reader...” (04:04)
• “These letters, so the attacker did not steal any data from you, they just hope to actually still get money.” (04:37)

Summary Table: Important Segments

| Timestamp | Topic | Key Points | |-----------|------------------------------------------|-----------------------------------------------------------------| | 00:08 | DShield Honeypot with ELK | New data analysis interface, tips on data management | | 01:16 | AMD CPU Vulnerability | Microcode update exploit, urgent patching, public exploit code | | 03:10 | VIM TAR Exploit | Vulnerability allows code exec via crafted archives, patch asap | | 04:18 | Snail Mail Ransomware Scam | Ransomware imposters using physical letters, likely fake |

Takeaways for Listeners

• Check out the new DShield ELK capabilities and blog post for honeypot data analysis.
• Verify your AMD CPUs have the latest microcode patch—public exploits now available.
• Patch VIM promptly against the TAR file vulnerability.
• Warn executives of fake snail mail ransomware threats; educate them on verification.

Stay safe, keep your systems updated, and be alert for cybersecurity threats both digital and analog!