Cybersecurity researchers have disclosed details of a vulnerability in OpenAI ChatGPT that leverages the artificial intelligence (AI) assistant's implicit trust in Markdown links and images to trigger prompt injections and open the door to phishing attacks. The technique has been codenamed ChatGPhish by Permiso Security. "The chatgpt.com response renderer trusts Markdown links and Markdown
An unknown threat actor has been observed using a large language model (LLM) agent to conduct post-compromise actions after obtaining initial access following the exploitation of a publicly-accessible Marimo network using a recently disclosed vulnerability. "The attacker compromised an internet-reachable Marimo notebook via CVE-2026-39987, extracted two cloud credentials from the compromised
A previously undocumented threat actor dubbed GREYVIBE has been attributed to ongoing and persistent attacks targeting Ukraine and Ukraine-related entities since at least August 2025. GREYVIBE, per WithSecure, is assessed to be a Russian-speaking group operating broadly in the Russian time zone, with the activities aligning with Kremlin state interests, specifically when it comes to
Shadow AI used to mean employees pasting things they shouldn't into ChatGPT. It now means something bigger: employees building full applications with AI, wiring them into production systems, and publishing them on the open internet. Without Security or IT in the loop. The artifact moved from a prompt to a product. The risk surface moved with it. In The Shadow Builders report (get it here), a
Cybersecurity researchers have discovered a malicious NuGet package that masquerades as a C# software development kit for Sicoob, one of Brazil's largest cooperative financial systems, to siphon client IDs and PFX certificates. According to Socket, versions 2.0.0 through 2.0.4 of "Sicoob.Sdk" contain functionality to exfiltrate sensitive information, including PFX certificates that are used to
The North Korean state-sponsored threat actor known as Kimsuky (aka Velvet Chollima) has been attributed to a fresh set of cyber attacks targeting South Korean military and corporate entities through March and April 2026. "Kimsuky employed a range of tailored social engineering tactics, such as spoofing security software installation pages and crafting a fake Webex meeting page that leveraged
A critical security vulnerability has been disclosed in Gogs, a popular open-source self-hosted Git service, that allows an authenticated user to execute arbitrary code under certain conditions. The security flaw, per Rapid7, is rated 9.4 on the CVSS scoring system. It does not have a CVE identifier. "The vulnerability allows any authenticated user to achieve remote code execution (RCE) on
Threat actors are continuing to exploit a critical, now-patched security flaw impacting FortiClient Endpoint Management Server (EMS) deployments to deliver credential-stealing malware. "The campaign abused trusted endpoint management infrastructure to deliver malware across managed endpoints," Arctic Wolf said. "Threat actors disguised the credential stealer payload as a Fortinet endpoint
Authorities in the Netherlands have arrested the co-owners of two related Internet hosting companies for operating IT infrastructure used by Russia to carry out cyberattacks, influence operations and disinformation campaigns inside the European Union. The two men were the focus of a 2025 KrebsOnSecurity story about how their hosting companies had assumed control over the technical infrastructure of Stark Industries Solutions, an Internet service provider sanctioned last year by the EU as a frequent staging ground for cyber mischief from Russia's intelligence agencies.
Lawmakers in both houses of Congress are demanding answers from the U.S. Cybersecurity & Infrastructure Security Agency (CISA) after KrebsOnSecurity reported this week that a CISA contractor intentionally published AWS GovCloud keys and a vast trove of other agency secrets on a public GitHub account. The inquiry comes as CISA is still struggling to contain the breach and invalidate the leaked credentials.
Canadian authorities on Wednesday arrested a 23-year-old Ottawa man on suspicion of building and operating Kimwolf, a fast spreading Internet-of-Things botnet that enslaved millions of devices for use in a series of massive distributed denial-of-service (DDoS) attacks over the past six months. KrebsOnSecurity publicly named the suspect in February 2026 after the accused launched a volley of DDoS, doxing and swatting campaigns against this author and a security researcher. He now faces criminal hacking charges in both Canada and the United States.
Until this past weekend, a contractor for the Cybersecurity & Infrastructure Security Agency (CISA) maintained a public GitHub repository that exposed credentials to several highly privileged AWS GovCloud accounts and a large number of internal CISA systems. Security experts said the public archive included files detailing how CISA builds, tests and deploys software internally, and that it represents one of the most egregious government data leaks in recent history.
Artificial intelligence platforms may be just as susceptible to social engineering as human beings, but they are proving remarkably good at finding security vulnerabilities in human-made computer code. That reality is on full display this month with some of the more widely-used software makers -- including Apple, Google, Microsoft, Mozilla and Oracle -- fixing near record volumes of security bugs, and/or quickening the tempo of their patch releases.
An ongoing data extortion attack targeting the widely-used education technology platform Canvas disrupted classes and coursework at school districts and universities across the United States today, after a cybercrime group defaced the service's login page with a ransom demand that threatened to leak data from 275 million students and faculty across nearly 9,000 educational institutions.
A Brazilian tech firm that specializes in protecting networks from distributed denial-of-service (DDoS) attacks has been enabling a botnet responsible for an extended campaign of massive DDoS attacks against other network operators in Brazil, KrebsOnSecurity has learned. The firm's chief executive says the malicious activity resulted from a security breach and was likely the work of a competitor trying to tarnish his company's public image.
A 24-year-old British national and senior member of the cybercrime group "Scattered Spider" has pleaded guilty to wire fraud conspiracy and aggravated identity theft. Tyler Robert Buchanan admitted his role in a series of text-message phishing attacks in the summer of 2022 that allowed the group to hack into at least a dozen major technology companies and steal tens of millions of dollars worth of cryptocurrency from investors.