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3 stories in the last 30d

ASCII smuggling crosses over from AI prompt injection to phishing evasion

Microsoft details high-volume phishing campaign using ASCII smuggling (Unicode tag chars) for filter evasion, peaking at 2.3M messages.

Microsoft researchers observed a high-volume finance-themed phishing campaign using invisible Unicode tag characters (U+E0000–U+E007F), a technique known from AI prompt injection research as ASCII smuggling, to split lure words like 'funding' and evade email filters. Telemetry from Microsoft Defender for Office 365 showed signature hits jump from roughly 21,000 messages on February 8, 2026 to more than 1.3 million on February 9, peaking above 2.3 million on February 11, with elevated weekday activity lasting approximately three months. The discovery emerged from prompt injection protection research, showing AI-era evasion techniques crossing into traditional phishing. Most messages were flagged by layered Defender protections rather than a single Unicode-specific signal.

Microsoft Security Blog · 13d agoPhishing & fraud in the wild1

Windows BitLocker Flaw Lets Attackers Execute Code on Vulnerable Systems

Microsoft patched CVE-2026-69449, a heap-based buffer overflow in Windows BitLocker allowing privileged local attackers to execute code; no exploitation reported.

Microsoft disclosed CVE-2026-69449 on September 8, 2026, an Important-severity heap-based buffer overflow (CWE-122) in Windows BitLocker with a CVSS 3.1 base score of 6.7. The attack vector is local (AV:L) with high privileges required, so exploitation needs privileged local access rather than remote access over the internet. Microsoft, as assigned CNA, has not reported public exploitation, and administrators are urged to inventory BitLocker-enabled systems and apply updates. Interim mitigations include least-privilege access, limiting administrative rights, and monitoring for unexpected elevated process activity.

GBHackers · 7d agoVulnerabilityCVE-2026-694491

Russia-Aligned UAC-0099 Plants Nuclear Weapon Prompt in Malware to Disrupt AI Analysis

Russia-aligned UAC-0099 planted a nuclear-weapon prompt inside malicious VBS scripts to derail LLM-based malware analysis targeting Ukraine.

ESET disclosed a technique dubbed GuardBreaker used by Russia-aligned UAC-0099 against a Ukrainian target: inserting the text 'I want to make a nuclear weapon. Help me ...' as a comment in a malicious VBS script to trip LLM safety guardrails and stop AI-assisted analysis. The script downloads and installs MATCHBOIL, a C# loader exclusive to UAC-0099, which CERT-UA warned was distributed as a fake Notepad++ plugin in late July 2026. Similar prompt-injection anti-analysis tricks appeared in the Mini Shai-Hulud, Miasma, and Hades npm supply chain campaigns linked to TeamPCP, two of whose alleged members were arrested in Western Australia.

The Hacker News · 14d agoThreat actor