The Hacker News | #1 Trusted Source for Cybersecurity News — Index Page

Cybersecurity researchers have disclosed a Microsoft 365 campaign that has been observed leveraging an adversary-in-the-middle ( AitM ) relay to capture sign-in sessions and then replay the stolen tokens to break into email accounts at 79 organizations. Huntress, which observed the activity between July 14 and September 22, 2026, said it detected 497 successful Microsoft 365 sign-in events across the victim organizations from over 200,000 login attempts, with the attackers ultimately compromising 97 accounts and registering 48 rogue Entra devices. "Rather than guessing passwords, the attacker replayed sign-in tokens stolen from victims, and we've traced more than 200,000 failed login attempts from the campaign window back to the 193.26.115[.]0/24 IP range," Huntress researchers Andrea Hatcher, Susannah Matt, Matt Poto, and Andrew Schwartz said. The attack has been found to employ an AitM login page, which sits between the victims and legitimate Microsoft infrastru...

An automated campaign is using stolen GitHub tokens to plant workflows that print a repository's secrets into its GitHub Actions logs, which the attackers then download before deleting the runs. The attacks have succeeded in private repositories and GitHub Enterprise environments, according to an analysis by cloud security company Wiz. A  GitHub safeguard  that pauses suspicious workflow runs stopped every public-repository run Wiz checked, but it does not cover private repositories or GitHub Enterprise Server. Each workflow sits on a new branch named ci-sync- followed by six random characters. Deleting a branch, or the run it started, does not undo the exposure. Every secret the repository could read should be rotated, and the token that pushed the branch revoked. Wiz has tracked the campaign since September 15 and calls it Gheist , after the user agent gheist that the attackers' tool sends with GitHub API requests. Wiz has recovered mor...

A malicious instruction file sitting in a developer's Downloads folder tried to make their AI coding agent install a known-malicious npm package, security firm Forever Security said in a report published last week. The company caught the attempt on a real customer's machine and stopped the agent before any code ran. It could not determine how the file got into the folder. The file was  AGENTS.md, a plain-text instructions file that a coding agent, such as OpenAI's Codex, reads when it starts in a folder and follows as directions. It was dressed up as ordinary engineering notes. One section told the agent to add a server to its own configuration and install a package called function-color from npm. That package is part of a malware campaign that other researchers have  documented separately : function-color pulls in a downloader called function-flag, which fetches and runs a Windows payload. Researchers at CloudSEK and Checkmarx, who ...

A single hacked device on a Tailscale network can be used to gain root access to other servers it can reach, according to a security researcher who published the findings this week. The attack requires two things: Tailscale SSH set up to allow port forwarding, and an attacker who already controls one device that the network's access rules permit to connect to the target. The findings were published on October 25 in a report called  Tailworm  by Erica Windisch of Cyberdione Labs. Windisch tested Tailscale version 1.104.2 and headscale version 0.29.5, the self-hosted server some networks use to run Tailscale instead of the company's hosted service, over three days in a lab. The report describes tests on that software, not attacks against real networks. As of publication, Tailscale had issued no  security bulletin , no CVE identifier, and no fixed version. Tailscale has responded in public. Mike Shaver, the company's vice president of engineering,  wrote on Red...

In an update, Palo Alto Networks Unit 42 said it's retracting its earlier assessment that the post-compromise activity targeting the European government agency involved the exploitation of the PHP2Shell flaws. "What researchers saw was an attack against a European government agency executed in the context of a vulnerable PHP application," a spokesperson for the company told The Hacker News via email. "This led us to believe that it was exploitation of those vulnerabilities. We are unable to confirm that initial access is associated with the specific PHP2Shell CVEs." The original story follows. Threat actors have been observed using agentic artificial intelligence (AI) platforms for post-exploitation activity following the abuse of the PHP2Shell vulnerabilities tracked as CVE-2026-109618 and CVE-2026-109619. "In one case, the attackers targeted a government entity in Europe and within two hours of the initial exploitation they had successfully acce...

OpenAI has announced plans to conduct frontier model training with no live internet access, as it resumes reinforcement learning (RL) training and internal inference of its most advanced AI models. "Based on the current state of alignment research, monitoring systems, and the security of internet infrastructure, we believe the responsible approach is to conduct frontier model training with no internet access," the artificial intelligence (AI) company said . "We've implemented this policy and will maintain it until advances in these safeguards justify broader internet access." OpenAI said models' growing capabilities can have the side effect of them getting much better at devising ways around environmental restrictions to escape containment and perform unintended actions. This can involve the model exploiting a software flaw or misconfiguration to reach the live internet, or finding unauthorized ways to communicate with agents in other sandboxes. Late ...

A memory-corruption flaw in Google's Brotli decoder sits in many programs that unpack Brotli-compressed data, among them Bun, Microsoft's .NET, the Python Brotli and brotlicffi packages, and Envoy proxies set up to decompress Brotli. Tracked as  CVE-2026-111497 , the flaw allows crafted compressed data to overwrite past the end of a buffer and corrupt a program's memory, potentially causing a crash, a memory leak, or the execution of attacker-controlled code. Imperva researchers have shown that code can run on one unpatched Node.js build . The same has not been demonstrated on the other software, and no real-world attacks have been reported. The flaw was  first disclosed on October 21 , when Node.js and Google shipped fixes, and more have followed product by product since. Because the bug is in Google's decoder and each program ships its own copy of it, every one has to update that copy on its own. Brotli is a compression format from Google, used ...

LiteLLM on Friday revealed that an Agent Platform master key accidentally published to a public GitHub repository in late May 2026 ultimately allowed the threat actor to push a malicious version of the popular Python package. "On May 27, 2026, a configuration file was committed to the public LiteLLM-Labs/lite-harness repository which inadvertently contained the master key to a deployment of the LiteLLM Agent Platform, an open source tool we use for orchestrating agents," LiteLLM's Oliver Jensen and Mateo Wang said . "The error was quickly identified, the commit force-pushed over, and we identified the exposed keys as requiring revocation. However, key revocation did not occur for the master key." LiteLLM said the unknown attacker (operating from "69.48.229[.]143") used this unrevoked key on October 10, 2026, to gain access to the Agent Platform and extracted a GitHub CLI OAuth token the service was configured with to allow self-hosted cloud a...

Google has updated its privacy policy to spell out that using personalized artificial intelligence (AI) features in Search or Gemini could allow the company to serve targeted ads to users based on their activity on other connected Google services. "You may choose to allow certain Google services, including services like Search or Gemini Apps, to access data from other Google services you use, such as Google Photos and Workspace apps like Gmail and Drive, in order to provide you with a more personalized experience, subject to the policies and settings of the accessing service," reads a policy update effective October 16, 2026. "For example, Search may process some of the data that you allow Search to access to personalize content, including ads." Google also notes in its revised policy that "We don't show you personalized ads based on your content from Drive, Gmail, or Google Photos, unless you choose to make data from these services available to ...