ZeroHour

Source: Elastic Security Labs

11 stories

The extension you never installed: KREMLIN forges Chrome's own integrity checks to steal banking sessions

Elastic details KREMLIN, a Brazilian banking malware whose malicious Chrome/Edge extension forges Chromium integrity checks to steal sessions.

Elastic Security Labs tracked operation REF9334 and its KREMLIN toolkit, a Brazilian banking malware campaign impersonating twelve banks across seven campaigns since May 2025. The infection chain uses multi-stage obfuscated JavaScript loaders with sandbox checks (file and process counting), scheduled-task persistence, and an Ethereum smart contract acting as a dead-drop resolver for C2 and payload URLs, abusing Archive.org for hosting. The malicious browser extension bypasses Chromium integrity mechanisms by manipulating Secure Preferences and regenerating required HMACs and App-Bound encrypted hashes. Threat Command disrupted over 1,500 infections by registering the kill-switch canary domain.

Elastic Security Labs · 1d agoMalware in the wild

Linux Detection Engineering - Local Privilege Escalation

Elastic details a layered detection framework for Linux local privilege escalation, covering 2026's copy-on-write bug wave and LLM-assisted discovery.

Elastic Security Labs describes how most Linux local privilege escalations share a common host flow — an unprivileged process launched from a writable path becoming root — and proposes layered detections combining general outcome-based rules with per-technique rules in Elastic Defend and Auditd. It tracks 13 recent LPE disclosures, seven of which share a copy-on-write/zero-copy bug class, including Copy Fail, DirtyFrag, Fragnesia, DirtyDecrypt, DirtyClone, pedit COW, and RefluXFS. Qualys attributes RefluXFS to an LLM-assisted research effort with Anthropic using Claude Mythos Preview, and another bug is credited to an LLM-assisted workflow. Detection and endpoint rules are published in Elastic's detection-rules and protections-artifacts repositories.

Elastic Security Labs · 4d agoResearch

Why 2026 is the Year to Upgrade to an Agentic AI SOC

Elastic Security Labs argues 2026 is the production inflection point for agentic AI in security operations centers.

Elastic Security Labs argues 2026 is the practical inflection point for agentic AI SOCs, noting nearly two-thirds of organizations are experimenting with AI agents while fewer than one in four have production deployments. The piece outlines operational challenges and recommendations: treat agents as non-human identities with least-privilege tool access, version-control system prompts as code, deploy unified agents with on-demand task packages, and enforce per-agent budgets and rate limits. It stresses explainability via RAG and transparent reasoning traces so analysts can verify and override autonomous decisions.

Elastic Security Labs · 7d agoIndustry

Data access: the hidden cost of security vendor lock-in

Elastic compares SIEM data egress cost, latency, and fidelity across CrowdStrike, Microsoft, Google, and Splunk, arguing vendors engineer lock-in.

Elastic Security Labs published an opinion piece comparing how major SIEM and security vendors handle data egress, based on each vendor's public documentation as of September 2026. It rates CrowdStrike Falcon Data Replicator and Palo Alto Networks XSIAM Event Forwarding as restricted (paid add-ons with batch delays), Microsoft as partially open, Splunk as open, and Elastic as open with no export license. The piece argues frictionless ingestion paired with licensed or delayed egress is an intentional lock-in business model, and cites CrowdStrike's 2026 Global Threat Report eCrime breakout time of 29 minutes to argue real-time telemetry access is now essential.

Elastic Security Labs · 11d agoIndustry

How to correlate Kubernetes audit logs with container runtime data

Elastic Security Labs shows how to join Kubernetes audit logs with Defend for Containers runtime data to investigate service account abuse and container escapes.

Elastic Security Labs demonstrates correlating Kubernetes audit logs with Defend for Containers (D4C) runtime telemetry in Elastic. In an Amazon EKS lab, a compromised workload service account performed discovery, read secrets, minted a token, created a privileged pod, and execed into it to attempt a container escape via nsenter and chroot. The escape wrappers appeared only in the decoded Kubernetes audit requestURI, not in runtime process events. The post covers join fields, prebuilt EQL sequence rules, and continues the control-plane correlation thread from the TeamPCP container attack scenario and the Hugging Face intrusion write-up.

Elastic Security Labs · 12d agoResearch1

REVSTEALER ramps up: analysis of up-and-coming infostealer

Elastic Security Labs analyzes REVSTEALER, an emerging infostealer harvesting browser credentials, cryptocurrency wallets, and gaming accounts.

Elastic Security Labs published a deep-dive analysis of REVSTEALER, described as an up-and-coming infostealer. The malware targets browser data, cryptocurrency wallets, and gaming accounts, with credential harvesting as its core function. The report tracks the family's capabilities as it ramps up activity in the wild.

Elastic Security Labs · 13d agoMalware in the wild

Linux Detection Engineering - Fileless Execution

Elastic Security Labs reproduces five Linux fileless execution patterns, including memfd_create staging and in-memory kernel module loads, and maps each to Elastic Defend rules.

Elastic Security Labs reproduced five Linux fileless execution patterns using its FENIX tooling: memfd_create staging, interpreter one-liners, deleted binaries, and in-memory kernel module loads. Each pattern is mapped to the Elastic Defend detection rules that catch it. The post is part of the team's ongoing Linux detection engineering series.

Elastic Security Labs · 14d agoResearch

From 88 lines to 1: Detecting DLL hijacking with Elastic Defend

Elastic condenses 88 lines of detection logic into one Elastic Defend 9.5.0 rule catching the DLL hijacking used by a ClickFix campaign.

The ClickFix campaign side-loads a malicious mscoree.dll next to a signed Microsoft binary and also ships a driver to kill Elastic Endpoint. Elastic rebuilt the DLL as a NativeAOT library, dropped it beside the signed binary, and confirmed that Elastic Defend 9.5.0 flags the load. The post replaces 88 lines of detection logic with a single rule for DLL search-order hijacking.

Elastic Security Labs · 18d agoTools in the wild

Inside Elastic's agentic SOC: How we took AI alert triage from 60% to 92% accuracy

Elastic's InfoSec team raised AI alert-triage accuracy from 60% to 92% using three self-correcting agents integrated into Slack triage.

Elastic's InfoSec team deployed three AI agents that read detection-rule investigation guides and closure reasons from 30 days of historical cases to triage alerts. The agentic pipeline lifted triage accuracy from 60% to 92%. Analysts now clear most alerts with a single click in Slack.

Elastic Security Labs · 21d agoTools

How a team of entity maintainers monitors, connects and scores entities in Elastic Security

Elastic Security explains how background 'maintainer' jobs build user, host and service entities from raw logs and drive identity resolution and risk scoring.

Elastic Security Labs describes the internal background jobs, called maintainers, that each own one piece of every user, host and service record in Elastic Security. The maintainers construct entities from raw logs, resolve identities across sources and compute risk scores, and the write-up explains how the team keeps this entity machinery consistent.

Elastic Security Labs · 22d agoTools

13 million tool calls: auditing every AI coding agent action with Elastic Agent

Elastic Security Labs shows how Cursor hooks plus Elastic Agent turn AI coding agent activity into 13 million huntable security events.

Elastic Security Labs demonstrates auditing AI coding agent behavior by pairing Cursor hooks with Elastic Agent, capturing every tool call, shell command, file read, and MCP request as structured events. The dataset of 13 million captured events can be hunted with ES|QL, giving defenders visibility into agent actions.

Elastic Security Labs · Aug 11, 2026AI safety & security1