Adobe Reader zero-day exploit used in months-long cyber campaign
Cybersecurity researcher Haifei Li discovered a malicious PDF that prompted a call for community analysis due to its unpatched and actively abused nature.
Zero-Day
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In Other News: Cyberattack Stings Stryker, Windows Zero-Day, China Supercomputer Hack
Other noteworthy stories that might have slipped under the radar: Jones Day hacked, Internet Bug Bounty program paused due to AI, new Mac stealer malware. Th...
Malicious PDF reveals active Adobe Reader zero-day in the wild
Hackers used an Adobe Reader zero-day for months. Researcher Haifei Li found a malicious PDF and asks the community to help analyze it.
Adobe Reader Zero-Day Exploited to Steal Data via Malicious PDFs
An Adobe Reader zero-day vulnerability is being actively exploited via malicious PDFs, allowing hackers to steal data without user interaction, with no patch...
Acrobat Reader zero-day exploited in the wild for many months
Unknown attackers have exploited a zero-day Adobe Acrobat Reader vulnerability since November 2025 and possibly even earlier, security researcher Haifei Li h...
Adobe Reader Zero-Day Exploited via Malicious PDFs Since December 2025
Threat actors have been exploiting a previously unknown zero-day vulnerability in Adobe Reader using maliciously crafted PDF documents since at least Decembe...
Hackers exploiting Acrobat Reader zero-day flaw since December
Attackers have been exploiting a zero-day vulnerability in Adobe Reader using maliciously crafted PDF documents since at least December. [.
Adobe Reader Zero-Day Exploited for Months: Researcher
Reputable researcher Haifei Li has come across what appears to be a PDF designed to exploit an unpatched vulnerability. The post Adobe Reader Zero-Day Exploi...
Anthropic Launches Claude Mythos Preview Focused on Zero-Day Vulnerability Discovery
Anthropic recently unveiled Claude Mythos Preview, a groundbreaking general-purpose language model demonstrating an unprecedented, emergent ability to autono...
Hackers Target Adobe Reader Users With Sophisticated Zero-Day Exploit
Security researchers at EXPMON have uncovered a highly sophisticated, unpatched zero-day vulnerability actively targeting Adobe Reader users. The exploit, fi...
The zero-day timeline just collapsed. Here’s what security leaders do next
A zero-day is not frightening because it is sophisticated. It is frightening because it is unknown.
Anthropic's Claude Mythos Finds Thousands of Zero-Day Flaws Across Major Systems
Artificial Intelligence (AI) company Anthropic announced a new cybersecurity initiative called Project Glasswing that will use a preview version of its new f...
Anthropic’s new AI model finds and exploits zero-days across every major OS and browser
Automated vulnerability discovery tools have existed for decades, and the gap between finding a bug and building a working exploit has always slowed attacker...
Immediate remediation of Fortinet FortiClient EMS bug ordered by CISA
BleepingComputer reports that the Cybersecurity and Infrastructure Security Agency has called on federal civilian executive agencies to remediate Fortinet Fo...
Fortinet releases emergency hotfix for FortiClient EMS zero-day flaw
Hackers have been exploiting a critical vulnerability in FortiClient Endpoint Management Server (FortiClient EMS) since at least the end of March. Fortinet h...
Windows zero-day vulnerability 'BlueHammer' exploit code released
The BlueHammer vulnerability is a local privilege escalation (LPE) flaw that combines a time-of-check to time-of-use (TOCTOU) vulnerability with path confusion.
Fortinet Releases Emergency Patch After FortiClient EMS Bug Is Exploited
Fortinet has updated its FortiClient EMS product after zero-day attacks surfaced
China-Linked Storm-1175 Exploits Zero-Days to Rapidly Deploy Medusa Ransomware
A China-based threat actor known for deploying Medusa ransomware has been linked to the weaponization of a combination of zero-day and N-day vulnerabilities ...
CISA Alerts Defenders to Actively Exploited Fortinet Zero-Day Vulnerability
The Cybersecurity and Infrastructure Security Agency (CISA) has issued an urgent warning regarding a critical zero-day vulnerability in Fortinet products. Th...
Windows Defender 0-Day Published Online, Giving Attackers Potential Full Access
A newly discovered zero-day vulnerability, dubbed “BlueHammer,” has been publicly disclosed. The flaw, which has been linked to Windows Defender, allows atta...