Daily Threat Briefing — May 31, 2026

📰 Cybersecurity News Headlines

Top stories from leading cybersecurity publications as of May 31, 2026.

1. Palo Alto GlobalProtect VPN auth bypass flaw now exploited in attacks
   — Bleeping Computer
   
   Palo Alto Networks is warning that hackers are now exploiting a PAN-OS GlobalProtect authentication bypass flaw, tracked as CVE-2026-0257, i…
2. New CIFSwitch Linux flaw gives root on multiple distributions
   — Bleeping Computer
   
   A newly discovered local privilege escalation vulnerability dubbed 'CIFSwitch' in the Linux kernel could allow attackers to forge CIFS authe…
3. PAN-OS GlobalProtect Authentication Bypass (CVE-2026-0257) Under Active Exploitation
   — The Hacker News
   
   Palo Alto Networks has warned that a recently disclosed medium-severity security flaw impacting PAN-OS and Prisma Access has come under acti…
4. Name That Toon: Mark of (Cybersecurity) Progress
   — Dark Reading
   
   As part of Dark Reading's 20th anniversary package, we asked readers for a cybersecurity-related caption that captures their thoughts about …
5. ChatGPT share links abused to host fake outage pages to deliver malware
   — Bleeping Computer
   
   Threat actors are abusing ChatGPT's content-sharing feature to display fake OpenAI outage pages that direct users to download malware disgui…
6. California AG sues 23andMe over 2023 breach exposing health data
   — Bleeping Computer
   
   California Attorney General Rob Bonta filed a lawsuit against 23andMe, now Chrome Holding Co., over the company's failure to protect sensiti…
7. ChatGPhish Vulnerability Turns ChatGPT Web Summaries Into a Phishing Surface
   — The Hacker News
   
   Cybersecurity researchers have disclosed details of a vulnerability in OpenAI ChatGPT that leverages the artificial intelligence (AI) assist…
8. Attackers Use LLM Agent for Post-Exploitation After Marimo CVE-2026-39987 Exploit
   — The Hacker News
   
   An unknown threat actor has been observed using a large language model (LLM) agent to conduct post-compromise actions after obtaining initia…
9. Asia's Cyber Insurance Market Shows Signs of Life
   — Dark Reading
   
   The cyber insurance industry has made relatively weak inroads into Asia due to a a variety of factors, but that could be changing.
10. With Complex Cloud Integrations, Small Errors Lead to Major Compromises
    — Dark Reading
    
    Researchers discover an exploit chain combining over-permissioned roles, secrets discovery, and non-human identities that could have comprom…
11. 'The Com' Cyberattacks Support Violence & Sexploitation
    — Dark Reading
    
    Your organization's security failures have consequences for everyone else too, since this neo-Nazi-infested criminal gang uses its cyber win…
12. New Russia-Linked GREYVIBE Targets Ukraine with AI-Powered Cyberattacks
    — The Hacker News
    
    A previously undocumented threat actor dubbed GREYVIBE has been attributed to ongoing and persistent attacks targeting Ukraine and Ukraine-r…

Generated by HiveNet.ai Threat Intelligence Platform · May 31, 2026 · Sources: The Hacker News, Bleeping Computer, Krebs on Security, Dark Reading, SANS ISC