We just published our research on escaping Firecracker microVMs, coordinated with AWS.

The interesting part is how a guest can end up accessing memory belonging to the Firecracker process running outside the VM.

The vulnerability: When a microVM is restored from a snapshot using the File memory backend, a failed memory remapping operation can leave KVM referencing a stale host virtual address range. Firecracker may subsequently reuse that memory for its own data, while KVM still considers it guest memory.

This allows a malicious guest to read or overwrite Firecracker VMM process memory, crossing the VM isolation boundary.

Our research demonstrates an exploit chain from guest userspace to controlled code execution in the host.

Affected configurations: Firecracker 0.23.0 - 1.16.1, when restoring snapshots with the File memory backend and a balloon or virtio-mem device.

Fixed: Firecracker 1.16.2 and 1.17.0+.

AWS advisory: https://aws.amazon.com/security/security-bulletins/2026-169-aws/

The write-up covers the vulnerability, the memory-management behavior behind it, and the exploitation process.

We are from Coinspect, the team behind the research. Happy to answer technical questions here.

Governments may retain the authority to police international finance, but the practical capability to identify, trace and interrupt illicit financial flows increasingly rests with privately held technology and financial sector companies. The latest RUSI Commentary examines the Binance heist, the role of private sector gatekeepers and whether the FATF is keeping up.

TL;DR: Our research team at Era uncovered Greeter, an attack framework targeting Flowise, an AI development platform with 55,000+ GitHub stars.

We deployed seven honeypots and captured 4,972 "hello" messages, each carrying malicious JavaScript through Flowise's overrideConfig parameter.

The interesting part? The malicious code never appeared in the saved workflow.

We reconstructed 4,000+ commands revealing:

• Host reconnaissance and privilege checks
• Searches for credentials, SSH keys, and secrets
• AWS, Azure, and GCP metadata probing
• Persistence attempts and fileless execution preparation

We also identified 4,372 internet-exposed Flowise instances, including 46 unauthenticated instances that appeared to match our vulnerable setup.

The bigger concern is how a compromised AI application can become an entry point into the broader cloud environment.

Full technical breakdown: https://era.security/blog/greeter-flowise-ai-infrastructure-attack

tl:dr;

• Contrary to popular belief among vendors, system integrators, and asset owners: network authentication in TETRA mission-critical radio networks does not provide authenticity & integrity guarantees at the individual message level.
• To make matters worse: base stations don't require a re-authentication whenever a radio is roaming from one cell tower to the next.
• This allows for traffic injection attacks: both voice and data. The latter is particularly worrying for SCADA WAN scenarios or where voice & alarming functionality can disrupt operations at such as at airports, harbors, railway operators, and civil defense siren systems.
• The 2026 attack on Taiwan High Speed Rail's TETRA network, leading to the emergency stop of several trains, shows a mild example of possible impact: https://www.midnightblue.nl/blog/analyzing-the-taiwan-high-speed-rail-thsr-tetra-cyber-incident-part-1

Had a subscription in the past with them and received the following e-mail:

Doesn't look like many sites have have picked up on this:

Dear cPGuard customers and partners,

An unidentified attacker targeted OPSSHIELD, gained unauthorized access to our licensing and update systems, and distributed a malicious script through the cPGuard update channel. **We have stopped further distribution of the script and released cPGuard 5.88.25 to remove the known backdoor and files left by the script.**

The script sent data to an endpoint on our licensing server under a compromised account. We secured that account as soon as we identified the breach and cleared our infrastructure credentials. We are investigating how the attacker gained access, which customer servers ran the script, and what data the attacker accessed.

**Please take the following actions immediately.**

1. **Update every cPGuard server.** Run `cpgcli update --start`. The corrective update removes the backdoor shell at `/var/tmp/.cpg91511_sh` and the collection directory `/var/tmp/.cpg91511`, including the password hashes and credential archive (`loot.tgz`) staged there.
   
2. **Verify the installed version.** After the update completes, run `cpgcli --version` on each server and confirm it reports **5.88.25**. If the update fails or the server still reports an older version (between 5.88.12 and 5.88.19), contact OPSSHIELD Support immediately.
   
3. **If you know or suspect the malicious script ran, reset passwords and revoke exposed credentials.** The script targeted `/etc/shadow`. Reset passwords for root and all other password-enabled local accounts from a trusted recovery environment. From a trusted device, change any passwords reused elsewhere and rotate affected database passwords, S3 access keys, DigitalOcean tokens, and secrets recorded in root's shell history. Replace SSH private keys stored under `/root/.ssh` and remove the corresponding old public keys from every system that trusts them. Complete this step even if the update succeeds, because credentials copied before cleanup may still be usable.

We are sorry that this breach put your systems at risk. If you need help assessing a server, please contact OPSSHIELD Support through your usual support channel. We will share further findings as we verify them.

The OPSSHIELD Team

(May 2026)

TL;DR:

• an email address like atouch${IFS}/tmp/savane-rce-proof@attacker.example gave any registered user code execution on its backend.
• From there, we made our account a superuser,
• impersonated Bash’s maintainer, and confirmed we could add an SSH key with push access to the upstream Bash repository.
• An unpatched kernel gave us root access and access to a GNU backup server. We reported it to the FSF on May 11, 2026.

FSF incident report: https://static.fsf.org/nosvn/security/savannah-20260807.pdf

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