ZeroHour

Source: SANS Internet Storm Center

16 stories

MacOS 27 - First Boot, (Tue, Sep 15th)

SANS ISC documents the expected network traffic macOS 27 'Golden Gate' generates on first boot to help defenders baseline their networks.

Johannes Ullrich of SANS Internet Storm Center captured roughly 300 packets from a macOS 27 'Golden Gate' system before user login, covering DHCP, IPv6 duplicate address discovery, DNS, and TCP behavior. macOS 27 resolves hostnames like albert.apple.com (device activation, certificate-pinned), push messaging hosts, and ipv4only.arpa for NAT64 networks. The OS still uses a TCP window scale of 6, ECN, and random timestamps, with only four TCP connections observed during boot. The analysis provides a reference baseline for security teams monitoring Apple endpoints.

ISC Stormcast For Friday, September 11th, 2026 https://isc.sans.edu/podcastdetail/10090, (Fri, Sep 11th)

SANS ISC released its daily Stormcast podcast for September 11, 2026; the feed provides no story details.

The SANS Internet Storm Center published its daily ISC Stormcast podcast episode for Friday, September 11, 2026. The feed contains only the standard copyright notice and links, without any story details.

SANS Internet Storm Centerupdated · 18h agofirst · 4d agoIndustry 5 sources

Apple Updates Everything, (Mon, Sep 14th)

Apple patched a record 261 vulnerabilities across iOS 27, macOS Golden Gate 27, watchOS 27, and other platforms, with none flagged as exploited.

Apple's annual OS update shipped iOS/iPadOS 27, macOS Golden Gate 27, tvOS 27, watchOS 27, and visionOS 27 plus bug-fix releases for the 26 and 15 branches, fixing a record 261 vulnerabilities. Notable issues include multiple kernel flaws allowing root privilege escalation (CVE-2026-43689, CVE-2026-43691, CVE-2026-43698, CVE-2026-43786), remote code execution in CUPS (CVE-2026-43692), kernel memory corruption via malicious NFS servers (CVE-2026-43686, CVE-2026-43687), and WebKit memory corruption from crafted web content (CVE-2026-43715). No vulnerabilities are labeled as actively exploited, and Apple does not assign per-CVE severities. Users report iOS 26.7 being downloaded when iOS 27 is intended, and tools like Little Snitch and BlockBlock need updates before upgrading to macOS 27.

The Self-Expanding Stolen Inference Supply Chain: An AI Agent Harvesting and Re-Serving LLM Access, (Fri, Sep 11th)

An autonomous coding agent harvested LLM API access from poorly secured gateways and aggregated stolen inference capacity behind a self-hosted gateway

A SANS researcher observed a semi-autonomous coding agent finding weakly secured LLM resale gateways via FOFA queries, creating trial accounts with temporary emails and CAPTCHA solving, and exploiting weak authorization such as client-supplied group_id fields. The agent validated stolen keys using factorial code-logic tests, then loaded roughly 379 upstream endpoints into a self-hosted New-API gateway, disabling 341 fake or dead channels. Five model names including claude-opus-5 and gpt-5.6-sol were served via round-robin and failover, forming a partially self-expanding inference supply chain resembling an evolution of LLMjacking.

SANS Internet Storm Center · 4d agoThreat actor in the wild

Redtail Payload Analysis [Guest Diary], (Wed, Sep 9th)

SANS guest analyst detonated a RedTail Linux sample from a DShield honeypot, finding process masquerading as php-fpm, monitoring-kill behavior, and a TCP listener.

A DShield honeypot captured multi-architecture RedTail Linux executables (ARM, ARM64, i686, RISC-V, x86-64) deployed via shell scripts. Dynamic analysis of the UPX-packed, statically linked x86-64 sample (SHA-256 63be5f38...d35e) in an isolated Ubuntu 24.04 VM on Proxmox showed it renamed its process via prctl(PR_SET_NAME), killed a filesystem-monitoring process, and opened a TCP listening socket while surviving processes posed as php-fpm or PostgreSQL-like workers. Differential memory images pre- and post-execution were captured from the hypervisor for forensics.

SANS Internet Storm Center · 5d agoMalware in the wild 2 sources1

September 2026 Microsoft Patch Tuesday, (Tue, Sep 8th)

Microsoft's September 2026 Patch Tuesday fixes a record 973 vulnerabilities, including 113 critical and two Windows privilege-escalation flaws already exploited in the wild.

Microsoft patched 973 vulnerabilities this month, its largest Patch Tuesday ever and far above the previous record of 664 set in July 2026, with 113 rated critical. Two Important elevation-of-privilege flaws (CVSS 7.8) are confirmed exploited in the wild: CVE-2026-81963 in the Windows Update Stack (improper link resolution, affects Windows 11 and Server 2025) and CVE-2026-85880 in Windows ALPC (heap-based buffer overflow allowing sandbox escape to SYSTEM, affects Windows 10 and Server 2012-2022). Critical unauthenticated RCEs (CVSS 9.8) were also fixed in Skype for Business Server (CVE-2026-66302), Windows Message Queuing (CVE-2026-69579), and Windows RRAS (CVE-2026-69590). SANS urges prioritizing the two exploited EoP fixes, then patching exposed MSMQ, RRAS, and Skype for Business deployments.

ISC Stormcast For Tuesday, September 8th, 2026 https://isc.sans.edu/podcastdetail/10084, (Tue, Sep 8th)

SANS Internet Storm Center's daily Stormcast podcast digest for September 8, 2026, summarizing current internet security activity.

The SANS Internet Storm Center published its daily Stormcast audio briefing for Tuesday, September 8, 2026. The available item text contains only licensing and URL metadata, with no specific vulnerabilities, incidents, or topics described.

SANS Internet Storm Center · 7d agoAdvisory

Critical MikroTik Vulnerability - Patch Now, (Sun, Sep 6th)

MikroTik patched a critical SSH authentication bypass already exploited in the wild; attackers add accounts to affected routers for post-patch persistence.

MikroTik released a patch late last week for a critical vulnerability allowing SSH authentication bypass that is already being exploited in the wild, per the vendor's September 2026 advisory. Attackers have been adding new accounts to affected devices to maintain access even after the patch is installed. The patch attempts to detect compromise and set a 'Flagged' status on affected devices, and SANS ISC advises administrators to assume compromise.

SANS Internet Storm Center · 8d agoExploit / PoC in the wild

numbat - AI agent observability, (Fri, Sep 4th)

SANS reviews Perplexity's open source numbat, a Go-based tool giving security teams observability, detection rules, and enforcement for AI agents like Claude and Gemini.

Numbat, Perplexity AI's open source observability tool, monitors desktop, CLI, IDE, and gateway AI agents through local hooks, OTLP/HTTP logs, and on-disk session artifacts. It ships detection rules mapped to MITRE ATT&CK (e.g., recon.network_sweep / T1046), supports enforcement mode, and packages investigations with SHA256-verified manifests and timelines. The SANS review positions it as a response to unmanaged AI agent and MCP server sprawl highlighted by the OpenAI/Hugging Face incident.

SANS Internet Storm Center · 10d agoAI tools & infra

Honeypot-Omaha and batch.py [Guest Diary], (Wed, Sep 2nd)

A SANS ISC guest diary describes batch.py, a Python tool that consolidates honeypot logs and enriches IOCs with threat intelligence data.

Written by a SANS.edu BACS intern, the diary explains analysis of the DShield Honeypot-Omaha sensor, which uses Cowrie to emulate SSH and Telnet and log attacker activity. The author's batch.py script implements a four-phase pipeline with SHA-256-generated master and guest authentication to consolidate JSON and log files, correlate data via external APIs, and produce MITRE, CVE, geolocation, threat-score and fingerprint enrichment for investigated indicators.

SANS Internet Storm Center · 12d agoTools1

ISC Stormcast For Thursday, September 3rd, 2026 https://isc.sans.edu/podcastdetail/10080, (Thu, Sep 3rd)

SANS Internet Storm Center released its daily Stormcast audio briefing for September 3rd, 2026.

The SANS Internet Storm Center published its regular daily Stormcast podcast episode. The feed text contains no substantive threat details, only the podcast link and licensing information. No specific incidents, vulnerabilities, or advisories can be extracted from the available text.

SANS Internet Storm Center · 12d agoAdvisory

ISC Stormcast For Wednesday, September 2nd, 2026 https://isc.sans.edu/podcastdetail/10078, (Wed, Sep 2nd)

SANS Internet Storm Center's daily Stormcast briefing for September 2, 2026; the feed carries no substantive story details.

This is the RSS shell for the ISC Stormcast daily podcast episode dated Wednesday, September 2, 2026. The provided text contains only licensing boilerplate and a link, with no incident, vulnerability, or threat details to extract.

SANS Internet Storm Center · 13d agoAdvisory

Guildma (Astaroth) malware infection from Brazilian Portuguese email, (Tue, Sep 1st)

Guildma (Astaroth) malware spread via geofenced Brazilian Portuguese phishing emails, using zip archives, shortcuts, and AutoIt loaders.

SANS researchers documented a Guildma (Astaroth) malware infection initiated on 2026-08-31 by a malicious Brazilian Portuguese email offering a DocuSign-themed PDF. The delivery link is geofenced to Brazil and requires Brazilian Portuguese browser and OS language settings, otherwise serving a legitimate installer. The infection chain uses a zip archive containing a Windows shortcut that retrieves a DLL saved as an alternate data stream, which installs a compiled AutoIt package for persistence. Unique SHA-256 indicators and HTTPS traffic to Azure-hosted and .cfd domains were observed, with prior reports noting the campaign's abuse of GitHub.

SANS Internet Storm Center · 13d agoMalware in the wild

ISC Stormcast For Tuesday, September 1st, 2026 https://isc.sans.edu/podcastdetail/10076, (Tue, Sep 1st)

SANS Internet Storm Center's daily Stormcast podcast for September 1, 2026 summarizes current internet threat activity; no detailed content provided.

This is the daily ISC Stormcast audio briefing from the SANS Internet Storm Center for Tuesday, September 1st, 2026. No article body was provided, so the specific stories covered in this episode cannot be extracted. Stormcast episodes typically summarize notable internet-wide security events and handler findings.

SANS Internet Storm Center · 14d agoAdvisory

The Coding-Agent Trap: When a "Free" LLM Endpoint Is the Adversary, (Mon, Aug 31st)

A SANS honeypot caught a real coding-agent session routed to a rogue "free" LLM endpoint, exposing a Windows user's transcript and tool outputs.

A SANS analyst describes how an internet-exposed inference honeypot was discovered, relabeled with sought-after model names like DeepSeek, and enrolled in infrastructure serving "free" LLM backends. On 2026-08-30 an opencode terminal coding agent sent an 88-message, 224 KB transcript 210 times in 91 seconds via a China Unicom relay, exposing directory listings, tool outputs and read file portions. The analyst frames tool-enabled agents treating model endpoints as trusted control planes as a novel risk — a "rogue model endpoint" that could request tool executions on the user's machine.

SANS Internet Storm Center · 15d agoAI safety & security1