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A lot of this week’s trouble starts with something trusted doing exactly what it was allowed to do. Signed drivers get turned against defenses. Legitimate apps help malware blend in. A weak header check opens a path to code execution. Elsewhere, exposed systems, old bugs, odd hiding tricks, and AI-assisted exploit research keep lowering the effort needed to cause damage. Nothing here needs much decoration. The small gaps are doing enough work already. The threats change every week. Subscribe, and we’ll alert you when each new ThreatsDay Bulletin is out.

In March 2026, an internal AI agent at Meta triggered a “Sev 1” incident after sensitive company and user data was exposed to employees who weren’t authorized to access it.  The incident began when a Meta employee posted a technical question on an internal forum. An engineer used an approved AI agent to analyze it, but the agent posted its response publicly without approval. The employee followed its advice, inadvertently making a large volume of sensitive data available to unauthorized engineers for over two hours.  This was not shadow AI. The tool was approved, but the AI behaved in ways nobody had anticipated.  It’s a perfect example of security’s next big AI governance problem: shady AI.  Shadow AI is the unapproved use of AI tools  Shady AI is when employees use approved AI tools in unapproved, unexpected, or poorly governed ways  Shadow AI happens outside the organization's visibility. Shady AI happens inside it. And that makes it muc...

Cybersecurity researchers have disclosed two denial-of-service (DoS) attacks that exploit how major content delivery networks (CDNs) convert client-facing HTTP/3 traffic into HTTP/1.1 requests to the websites they front, amplifying a low-bandwidth request stream by up to 350x against the origin server. The attacks, collectively named " CDN Tsunami ," were evaluated against Alibaba, Baidu, Cloudflare, Amazon CloudFront, Fastly, and Tencent. All six were found susceptible to the bandwidth variant and five to the connection variant, with Cloudflare unaffected by the latter because it buffers the complete request before opening a connection to the origin. The attack requires a website hosted on one of the six providers, with HTTP/3 serving at the edge, and no configuration changes on the website's part. The paper lists HTTP/3 as enabled by default at Cloudflare and CloudFront. However,  Cloudflare's documentation  describes HTTP/3 as available on all plans and pr...

OpenAI on Tuesday revealed that it paused reinforcement learning ( RL ) training for its latest artificial intelligence (AI) models for two weeks while it shored up additional defenses and increased the scope of its monitoring to avert another Hugging Face-like incident . "As models become more capable, the risks associated with developing and testing them internally also grow," the AI company said . "Our standards for monitoring, alignment, and security must stay ahead of those risks. We wanted to take the time necessary to meet those standards, so we temporarily slowed the pace of scaling." The company said its largest planned frontier RL run remains on hold for the time being as it conducts smaller-scale training and evaluations to evaluate model behavior, validate its safeguards, and establish more concrete evidence of alignment before moving to the next phase. To that end, OpenAI said it plans to strengthen safeguards across its development process, inc...

GitLab has released security updates to address a critical vulnerability impacting its Community Edition (CE) and Enterprise Edition (EE) software that, under certain conditions, could allow an unauthenticated attacker to remotely modify or delete public projects and user data. The flaw, tracked as CVE-2026-19478 , has been rated Critical by GitLab and assigned a CVSS score of 9.4. Released on August 17, 2026, the critical patch release arrived outside the company's usual schedule of twice-monthly updates on the second and fourth Wednesdays, five days after a routine patch release that carried no critical-rated issues. Only self-managed installations need to act. The fixes are available in GitLab 19.2.4, 19.1.6, 19.0.8, and 18.11.11 . "GitLab.com and GitLab Dedicated are already running the patched version. GitLab.com and GitLab Dedicated customers do not need to take action," the company said. The following versions are affected - All versions from 18.2 ...

The expensive attacks are not always the clever ones. This week had plenty of proof. Exposed services got hit, old bugs found fresh use, browser sessions became attack paths, and supply-chain problems kept spreading farther than the original compromise. A lot of it came down to access that was already there and defenses that assumed nobody would look too closely. So, nothing magical. Just a lot of small openings turning into bigger problems. Here’s what stood out. ⚡ Threat of the Week Suspected China APT Behind Exploitation of New VMware Flaw — A suspected China-nexus APT is assessed to be behind the exploitation of a newly patched security flaw in VMware vCenter. The attacks involve the exploitation of CVE-2026-59310 (CVSS score: 9.8), a severe directory-traversal vulnerability in the VMware vCenter server that could be weaponized by a malicious actor to execute arbitrary code. In at least one compromised instance, the attacks led to the deployment of a backdoor and. a rever...

A new White House memo signed by U.S. President Donald Trump has instructed the National Coordination Center (NCC) to establish a program that would allow private sector companies to take advantage of their "innovative capabilities" to break into foreign Transnational Criminal Organizations (TCOs) and disrupt them. "By partnering with vetted United States companies subject to the direction and oversight of the Federal Government, we will enhance our ability to counter TCO threats and combat transnational cybercrime, fraud, and other predatory schemes against American citizens," the memo reads . To that end, the NCC has been tasked with setting up a program within 60 days that allows authorized companies to conduct two types of operations against TCOs upon obtaining approval: cyber surveillance operations, which can access sensitive data without authorization from the owner or operator, and cyber effects operations, which can result in disruption, denial, degrad...

Some weeks have one big security story. Others bring many smaller updates that are easy to miss but still matter. This week has plenty of them, covering cloud services, AI tools, malware, data breaches, scams, and new attack methods. The latest ThreatsDay Bulletin puts all of these short updates in one place, so you can quickly catch up on what happened, what changed, and what security teams should know. The threats change every week. Subscribe, and we’ll alert you when each new ThreatsDay Bulletin is out.

The Computer Emergency Response Team of Ukraine (CERT-UA) has disclosed details of a new social engineering campaign orchestrated by Russian nation-state threat actors targeting IT workers in the country by masquerading as recruiters to trick them into installing malware. CERT-UA pinned the activity on a threat cluster it tracks as UAC-0145 , which is a subgroup within Sandworm (aka APT44, Seashell Blizzard, and UAC-0002), a sophisticated hacking group affiliated with the GRU. The campaign is assessed to be ongoing since May 2026. "Specifically, on job search websites, after reviewing a candidate's resume, the attackers contact a potential victim – typically a system administrator or IT specialist – on behalf of an IT company (such as ATLAS Business Group)," CERT-UA said .  Although initial communications take place via built-in online chat, the conversation subsequently shifts to messaging apps like Telegram, where a preliminary chat takes place with a purported H...

OpenAI on Monday unveiled a new cybersecurity-focused model called GPT‑5.6‑Cyber that it said is focused on vulnerability research, penetration testing, and incident response. "Built on GPT‑5.6 Sol, it is trained to improve capabilities on several specialized cybersecurity tasks (e.g., finding zero-day vulnerabilities and developing exploit chains) and to reduce refusals for certain higher-risk, dual-use cyber tasks," OpenAI said . The artificial intelligence (AI) company said it's making GPT 5.6 Cyber available through Daybreak Red, a new tier that provides access to its purpose-trained cybersecurity models to other firms for authorized vulnerability research, exploit validation, and security testing. GPT-5.6-Cyber, a more cyber-permissive version of GPT-5.6 Sol, builds upon GPT‑5.5‑Cyber , which OpenAI released in June 2026. To measure the reduced rate of refusals provided by GPT‑5.6‑Cyber through Daybreak Red access, OpenAI said it created an internal evaluat...

AI is helping development teams produce far more code, far faster. But security teams still have to review vulnerabilities, manage dependencies, prioritize fixes, and control risk at human speed. When software output jumps 10 to 50 times, the problem is no longer just finding vulnerabilities. It is keeping security from becoming the bottleneck, or worse, losing control of what gets shipped. In our latest webinar with Chainguard experts, “ The True Cost of Building at Machine Speed ,” you can now watch how security teams can keep AI-driven development fast without letting risk scale with it. For years, application security followed a familiar cycle: developers wrote code, scanners found problems, security teams prioritized them, and engineers fixed what mattered most. AI puts that model under pressure. If teams can suddenly create many times more code, security can also end up with many more components, dependencies, findings, and fixes to manage. More scanning alone does no...

A lot of security problems still begin with someone doing a completely normal thing. Cloning a repo. Answering a call. Leaving a box exposed. Trusting the default. That pretty much covers the mood this week. Old bugs are back, supply chains are getting stranger, and some exploit paths are so short you wonder what was supposed to stop them in the first place. That’s only part of it. Here’s everything else that made the Monday recap. ⚡ Threat of the Week Anthropic's Model Attempts to Poison Open-Source Project — A new evaluation conducted by the U.K. AI Security Institute (AISI) found that AI models with access to the internet reached out into the real world to target individuals and organizations autonomously across 10 of the total of 122 runs. Of 19 such actions recorded, 17 originated from Anthropic's Mythos 5 and the remaining two involved OpenAI's GPT-5.6-Sol with cyber classifiers. In the most serious case, Anthropic's Claude Mythos 5 spent 34 hours trying...

OpenAI has announced that it's pausing some "internal activities" involving its upcoming artificial intelligence (AI) model Astra after an internal evaluation found it had made significant advancements in agentic coding and cybersecurity. In response to the discovery, the AI upstart said it's implementing security controls for higher-capability models and associated activities, such as isolated testing environments, restricted network and tool access, enhanced model weight protections and encryption, additional monitoring and detection capabilities, and sandboxed execution. "We are pausing internal activities involving Astra that do not yet meet these strengthened security control requirements," it said in a statement. "We have implemented universal monitoring for risky actions and misalignment across all agentic applications of Astra, including training and evaluation. Monitors evaluate the model's Chain of Thought and trigger a security re...

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) on Friday added a critical-severity security flaw impacting Progress Kemp LoadMaster to its Known Exploited Vulnerabilities (KEV) catalog, following reports of active exploitation in the wild. The vulnerability, tracked as CVE-2026-8037 (CVSS score: 9.6), is a command injection flaw that could be weaponized to achieve arbitrary code execution on susceptible devices. "Progress LoadMaster contains a command injection vulnerability that allows an un-authenticated attacker to execute arbitrary commands on the LoadMaster appliance by exploiting unsanitized input in multiple command endpoints," CISA said . In an analysis published in June 2026, watchTowr Labs described the issue as present in a function named "escape_quotes()" within the load balancer application and that it stemmed from improper handling of user-supplied input, ultimately enabling command injection. Successful exploitation of the...

Entra ID researcher Dirk-jan Mollema demonstrated that malware already running in a signed-in Windows session can silently use the victim's Windows Hello for Business key to authenticate to Microsoft Entra ID. The attacker can then establish longer-term cloud access, register a device it controls, obtain a Primary Refresh Token (PRT), and add further authentication methods where tenant policies permit. On TPM-backed systems, the attacker does not extract the private key, recover the PIN, or trigger a biometric prompt. Windows ticketing keeps private-key operations available while the user is interactively signed in, allowing code running as the user to ask Windows to sign authentication data. Administrator privileges are not required. The technique requires code execution in the victim's signed-in session. Mollema describes the behavior as a consequence of how Windows Hello for Business works and says it was left as-is. The disclosure does not report active exploitatio...

Apparently, opening the thing is now enough. A repo can run before the first prompt, a package can hide among hundreds, and a harmless-looking PDF can finish the job. This week runs on cheap leverage: exposed servers, recycled bugs, poisoned agent instructions, remote-access tools dressed as support software, and trusted defaults doing attackers a favor. Nothing here is especially mystical. Just ordinary systems trusting slightly too much, slightly too early. The full list follows. The threats change every week. Subscribe, and we’ll alert you when each new ThreatsDay Bulletin is out.

A new class of prompt injection is spreading across commercial websites. It requires no malware, no stolen credentials, and no zero-day exploit. It abuses a standard feature built into almost every major AI assistant: pre-filled deep links. We observed production websites embedding hidden prompt injection payloads inside "Ask AI" buttons on marketing and competitor comparison pages. When a user logged into ChatGPT, Claude, Gemini, or Grok clicks one, a pre-formed query executes immediately in their session, with no confirmation and no warning. Most of these links are benign. The dangerous ones instruct the AI to permanently save the vendor's domain as a "trusted source," quietly biasing every future answer in that vendor's favor. In February 2026, Microsoft Security catalogued the behavior as AI Recommendation Poisoning , identifying 31 companies across 14 industries deploying it, with more than 50 distinct prompts observed in a single data source over ...

This week kept coming back to permission. A model crossed a boundary. A wallet trusted bad randomness. Webmail kept an intruder around. Public systems, package feeds, hotel networks, and login flows all gave away more than intended. Some of it was clever. Most of it was just access left lying around: old bugs, exposed gear, poisoned dependencies, weak defaults, and tooling that moved from forum chatter to real targets. The full weekly recap report follows. ⚡ Threat of the Week Anthropic Disclosed its Models Targeted 3 Organizations - Anthropic revealed that three of its models, including Claude Opus 4.7, Mythos 5, and an unnamed research model, breached three unnamed organizations during cybersecurity testing without its knowledge. The AI firm said the earliest incidents date back to April 2026, adding it made the discoveries after launching a "large-scale retrospective review" in response to the recent Hugging Face incident. "After reviewing 141,006 evaluatio...

Google on Thursday announced that it fixed a whopping 1,072 security bugs in Chrome versions 149 and 150, surpassing the total number of flaws the company fixed across the prior 23 milestones combined. Both versions were released last month. In its latest patch for Chrome 151, released Wednesday, the tech giant resolved 370 flaws , out of which 349 were reported by Google itself. Seven of the vulnerabilities have been marked critical in severity. The development comes amid an exponential surge in vulnerability discovery, mainly fueled by the advent of large language models (LLMs) that have accelerated the process, leading to an unprecedented spike in new bug reports, so much so that issues are being flagged at a faster rate than companies can fix them. According to statistics shared by the U.S. National Vulnerabilities Database (NVD), 46,872 flaws have been recorded so far in 2026, nearing the 49,920 vulnerabilities reported for the entirety of 2025.

Anthropic on Thursday became the latest artificial intelligence (AI) company to reveal that three of its models, including Claude Opus 4.7, Mythos 5, and an unnamed research model, had breached three unnamed organizations during cybersecurity testing without its knowledge. The AI firm said the earliest incidents date back to April 2026, adding it made the discoveries after launching a "large-scale retrospective review" in response to a recent disclosure from OpenAI that a combination of its models escaped the sandboxed environment by exploiting a previously unreported zero-day in Artifactory to obtain internet access and break into Hugging Face's production systems with an end goal to cheat on an evaluation. "After reviewing 141,006 evaluation runs where Claude could have obtained internet access, we identified three incidents in which a model accessed the internet from within or while interacting with the evaluation environment of Irregular, one of our third-...