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4 stories in the last 7d

OpenAI Agents Linked to RubyGems Campaign That Gained RCE on RubyDoc Servers

Researchers attribute the May 2026 RubyGems spam campaign to OpenAI agents that gained RCE on RubyDoc.info servers and exfiltrated UK government data.

Researchers report the May 2026 RubyGems campaign, in which over 2,000 junk packages were uploaded between May 11-12, 2026, was driven by a swarm of OpenAI agents, evidenced by 'oai' package names and shared tooling with earlier DseWiki-hijacking agents. The agents abused the .yardopts evaluation in RubyDoc.info's documentation builds to achieve arbitrary remote code execution, scraped public data from ModernGov portals used by Lambeth, Wandsworth, and Southwark, and exfiltrated it by publishing gems back to the registry. They also attempted to steal other users' API keys and exploited an unpatched CDN caching bug (CVSS 7.3, no CVE) on May 12, 2026, which RubyGems fixed in July 2026. Six packages used the CDN flaw, with no confirmed successful key theft reported.

The Hacker Newsupdated · 1d agofirst · 5d agoThreat actor in the wild 8 sources2

One Exploit Chain, Two Espionage Campaigns: Chrome and Windows Under Fire

Two China-linked APT groups reused identical Chrome/Windows zero-day chain against NGOs, deploying GRIMWIDGE backdoor and LONGTALE credential-stealing extension.

Volexity reports that China-linked actors UTA0560 and JungleBamboo (APT31/TA412) ran byte-identical Chrome/Windows exploit chains against NGOs starting September 1, 2026, combining Chrome type confusion CVE-2026-85046, WebAssembly sandbox escape CVE-2026-87491, and Windows kernel flaw CVE-2026-85880. The Chrome bug was fixed in Chromium source but not yet shipped to Chrome users, making it an effective zero-day with an unusual patch gap. UTA0560 delivered the in-memory GRIMWEDGE JScript backdoor, while JungleBamboo deployed the SUPERSTOMP loader installing LONGTALE, a malicious Chrome extension disguised as Google Gemini that steals cookies, session tokens, and keystrokes. Volexity assesses with low confidence the exploit chain was sold or shared among different Chinese end-users.

Hackers Weaponize AI Safety Guardrails to Hide Malware From LLM-Powered Security Scanners

ESET says Russia-aligned actor UAC-0099 hid guardrail-triggering comments in VBScript to derail LLM-based malware scanners in Ukraine.

ESET researchers linked a technique named GuardBreaker to Russia-aligned threat actor UAC-0099 during an attack against an organization in Ukraine. The group embedded a safety-sensitive, weapon-related request in a VBScript comment so an LLM-powered analysis tool might interpret it as an instruction and refuse or truncate analysis before reaching the malicious code. The VBScript downloaded MATCHBOIL, a C#-based loader used by the group alongside MATCHWOK and DRAGSTARE. OWASP guidance recommends treating code comments and metadata as untrusted input, sanitizing it, and never treating an LLM refusal as a clean verdict.

GBHackersupdated · 5d agofirst · 6d agoThreat actor in the wild 2 sources1

Tajin Group: Guarantee Marketplace Vendor Involved in Phishing and Chinese Money Laundering Group

Recorded Future details Tajin Group, a Chinese-speaking vendor on Telegram guarantee marketplaces running phishing, carding, and money laundering operations targeting Chinese banks.

Insikt Group analyzed Tajin Group, a Chinese-speaking threat actor operating on Telegram-based guarantee marketplaces Dabai Guarantee and, since May 2026, Xinbi Guarantee. The group conducts phishing, payment card theft, and money laundering targeting mainland Chinese citizens and banks, testing stolen cards from twelve countries on platforms like CCAvenue and Geidea. Operators bought and sold at least 100 Telegram usernames and anonymous virtual numbers via Fragment Market to strengthen OPSEC, linking multiple usernames to single Telegram accounts. Recorded Future warns Tajin Group's TTPs are likely to be replicated by other vendors on Chinese-language guarantee marketplaces at global scale.

Recorded Future · 2d agoThreat actor