Cybersecurity Brief – 2026-09-23
Major Incidents or Breaches
- The ShinyHunters cyber extortion group claims to have breached the US Federal Bureau of Investigation, stealing data on current and former employees and job applicants. The group states it exploited a zero-day vulnerability in Oracle PeopleSoft to access internal services and exfiltrate sensitive data. ShinyHunters is demanding the FBI retract a report describing its tactics and threatens to leak the stolen information if demands are not met [10][24][50][52].
- Threat actors stole 170 private repositories from cybersecurity firm CrowdSec by leveraging an OAuth token obtained through the TanStack npm supply chain attack on a former employee’s computer [35].
- Sweden’s data privacy regulator fined IT provider Miljödata $183,000 for insufficient security measures that led to a breach in August 2025, affecting 2.2 million individuals [22].
Newly Discovered Vulnerabilities
- F5 disclosed and patched a critical zero-day vulnerability (CVE-2026-94127) in BIG-IP Access Policy Manager (APM) that allows unauthenticated attackers to execute remote code on affected systems. The flaw was actively exploited in attacks targeting OAuth servers [7][20][49].
- Check Point released emergency fixes for a zero-day vulnerability (CVE-2026-93616) in its Security Management Server, which allowed attackers in targeted attacks to upload and execute arbitrary scripts [11][27][51].
- Arista Networks patched a zero-day vulnerability in VeloCloud Orchestrator (VCO) On-Prem deployments, which was being actively exploited to allow remote attackers access to privileged internal functionality [17][48].
- A new cPanel flaw in the CalDAV and CardDAV services enables any hosting account holder to execute code as root, granting full server control [3].
- A critical vulnerability in Bifrost, an open-source AI gateway, allows unauthenticated attackers to execute arbitrary commands on the server without credentials [15].
- A use-after-free vulnerability in the Linux kernel’s AF_UNIX socket subsystem enables container escape and host root access. An exploit has been released and the flaw remains unpatched in Ubuntu [6].
- WordPress patched a critical flaw in its core software that allowed unauthenticated attackers to load arbitrary PHP files from outside theme folders, potentially leading to remote code execution on some servers [12].
- Next.js disclosed a critical ImageResponse vulnerability that can lead to server code execution via crafted SVG input [9].
- Adobe released patches for nine critical vulnerabilities in Connect and AEM Forms that could be exploited for arbitrary code execution and privilege escalation [43].
- Google Chrome 154 patched 108 vulnerabilities, including several rated critical for memory safety and memory corruption [45].
Notable Threat Actor Activity
- A Chinese state-linked threat actor (UTA0565) exploited a zero-day exploit chain in Google Chrome and Microsoft Windows via fake websites to deploy CLEANGULP malware, targeting victims with advanced techniques [8].
- Chinese-speaking threat actors have been exploiting vulnerabilities in Zyxel GS1900 Smart Managed Switches and WordPress to steal sensitive government data from nearly 1,000 devices and over 18,500 records [23].
- The EvilTokens phishing-as-a-service platform, which compromised more than 12,000 Microsoft accounts at over 10,000 organizations using AI-driven attack chains, was disrupted in a coordinated takedown by Microsoft, which seized 50 websites and disabled over 150 domains [14][28][33][44].
- A malicious npm package (“tw-pkgprobe-7731”) posed as a Twilio bug-bounty probe to target developers, enabling credential exfiltration [13].
- A new Windows malware, ClosedQuorum, uses multiple AI models (Google Gemini, DeepSeek, Qwen, Mistral) to autonomously determine post-compromise actions [25].
- The Ryuk ransomware group member was sentenced to 24 months in prison for attacks on US companies [19].
- Threat actors exploited a stolen OAuth token from a former employee to access CrowdSec’s private GitHub repositories [35].
Trends, Tools, or Tactics of Interest
- An AI-assisted phishing campaign sent over one million personalized emails attempting payment diversion scams, demonstrating the growing use of AI in large-scale phishing operations [1].
- AI is increasingly being leveraged in both attack (e.g., phishing, malware decision-making) and defense (e.g., autonomous security agents), with new tools emerging to benchmark and control AI agent performance [4][5][25][36][44][47].
- Attackers with privileged access can register rogue external MFA providers to steal user passwords during legitimate login attempts [21].
- More than 80,000 AI relay servers are being used to mask Chinese access to frontier AI models in the US, likely to facilitate model cloning [31].
- A proof-of-concept zero-day tool, BigDiskBuster, was released that can block Microsoft Defender updates by filling available disk space [16].
- The Cybersecurity and Infrastructure Security Agency (CISA) published guidance on deception techniques to help organizations set traps for cybercriminals [34].
- Shadow IT remains a challenge, with tools like Wazuh recommended to improve visibility of unmanaged endpoints and unauthorized assets [26].
- Honeywell research indicates that while 88% of OT security leaders consider their programs mature, only 21% have a complete OT asset inventory, and full autonomy in OT security remains rare [42].
Regulatory or Policy Developments Affecting the Security Industry
- Sweden’s IMY imposed a significant fine on Miljödata for inadequate data protection, reinforcing regulatory expectations for IT service providers handling large volumes of personal data [22].
Sources#
- ShinyHunters Claims FBI Breach, Says It Stole Data on Agents and Job Applicants - thehackernews.com
- ShinyHunters claims FBI hack, data theft in PeopleSoft zero-day breach - bleepingcomputer.com
- ShinyHunters Claims FBI Hack, Demands Retraction of Threat Report - securityweek.com
- ShinyHunters claims FBI breach was revenge for “false” report - malwarebytes.com
- Shai-Hulud Attack Nips Cyber-Firm CrowdSec's GitHub Data - darkreading.com
- Sweden fines Miljödata $183,000 over breach affecting 2.2 million - bleepingcomputer.com
- F5 Patches Critical BIG-IP APM Zero-Day Exploited for Unauthenticated RCE on OAuth Servers - thehackernews.com
- F5 patches BIG-IP APM zero-day flaw exploited in RCE attacks - bleepingcomputer.com
- Critical F5 BIG-IP Vulnerability Exploited as Zero-Day - securityweek.com
- Check Point Warns of Management Server Zero-Day Exploited in Targeted Attacks - thehackernews.com
- Check Point warns of Management Server zero-day exploited in attacks - bleepingcomputer.com
- Check Point Patches Exploited Management Server Zero-Day - securityweek.com
- Arista patches actively exploited VeloCloud Orchestrator zero-day - bleepingcomputer.com
- Arista Urges Immediate Patching of Exploited VCO Zero-Day - securityweek.com
- New cPanel Flaw Lets a Hosting Account Run Code as Root, Take Full Server Control - thehackernews.com
- Critical Bifrost AI Gateway Flaw Lets Attackers Run Commands Without Credentials - thehackernews.com
- Exploit Released for Unpatched Ubuntu Linux Flaw Enabling Host-Root Container Escape - thehackernews.com
- WordPress Issues Patch for Critical Flaw That Can Enable Code Execution on Some Servers - thehackernews.com
- Critical Next.js ImageResponse Flaw Can Lead to Server Code Execution via Crafted SVG Input - thehackernews.com
- Adobe Patches Critical Flaws in Connect, AEM Forms - securityweek.com
- Chrome 154 Patches 108 Vulnerabilities - securityweek.com
- Chinese Hackers Exploit Chrome-Windows Zero-Day Chain to Deploy CLEANGULP Malware - thehackernews.com
- Chinese hackers exploit WordPress, Zyxel flaws to steal govt data - bleepingcomputer.com
- Microsoft Takes Down EvilTokens Device-Code Phishing Service Tied to 12,000 Inbox Compromises - thehackernews.com
- EvilTokens PhaaS disrupted after compromising 12,000 Microsoft accounts - bleepingcomputer.com
- Microsoft Disrupts EvilTokens Device Code Phishing Service - darkreading.com
- AI-Powered Phishing Platform EvilTokens Disrupted by Microsoft - securityweek.com
- Malicious npm Package Poses as Twilio Bug-Bounty Probe, Can Exfiltrate Credentials - thehackernews.com
- New ClosedQuorum Windows malware uses AI for attack decisions - bleepingcomputer.com
- Ryuk ransomware member sentenced to 24 months in prison - bleepingcomputer.com
- AI-Assisted Phishing Campaign Sent Over A Million Personalized Emails - blog.knowbe4.com
- 545 Hackers Tested It First. Now XRanges for AI Scores Your Security Agent - thehackernews.com
- Anthropic and OpenAI Models Still Attempt Restricted Actions in Safety Tests - thehackernews.com
- Amid Ongoing Rogue Incidents, Debate Over AI Safety Gets Real - darkreading.com
- Outerlimit Raises $16 Million to Stop Rogue AI Agents From Causing Harm - securityweek.com
- Rogue external MFA providers can steal passwords during logins - bleepingcomputer.com
- Relays Are Masking Chinese Access to Frontier AI Models in the US - darkreading.com
- Researcher Drops BigDiskBuster Zero-Day PoC That Blocks Microsoft Defender Updates - thehackernews.com
- Deception by Design: CISA's Guide to Tricking Cybercriminals - darkreading.com
- Reducing shadow IT visibility gaps with Wazuh - bleepingcomputer.com
- Honeywell: OT Security Teams Embrace AI, but Autonomy Still Rare - securityweek.com