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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 · 12d agoPhishing & fraud in the wild

Phishing Campaign Sends Millions of Emails Using Invisible Unicode to Evade Filters

Microsoft warns of a high-volume phishing campaign using invisible Unicode characters to split keywords like 'funding' and evade filters, peaking at 2.37 million daily messages.

Microsoft's Security Research team documented a high-volume phishing operation inserting deprecated Unicode Tags characters (U+E0000-U+E007F) inside financial keywords such as 'funding' so literal-string and regex email filters stop matching them. The campaign ran on a weekly cadence with 1-2.37 million weekday messages between February and May 15, 2026, peaking on February 26, 2026. It used hundreds of disposable finance-themed sender domains and relayed mail through ActiveCampaign's click-tracking infrastructure (acemlnd[.]com, activehosted[.]com), lending legitimate platform reputation. Microsoft ties the activity to an AI-assisted SBA loan phishing campaign that Fortra's FIRE team disclosed in September 2025.

The Hacker News · 11d agoPhishing & fraud in the wild

ASCII smuggling isn't just an AI security risk

Microsoft tracked a phishing campaign peaking at 2.37 million daily messages that hid financial-lure keywords with invisible Unicode tag characters to evade filters.

Microsoft researchers uncovered a large phishing campaign that inserted invisible Unicode tag characters (e.g., U+E0020) inside common financial keywords like 'funding', splitting words so keyword, signature, and regex matches fail. The campaign peaked at more than 2.37 million messages in late February 2026, ran from about 150 finance-themed sender domains on a strict weekday-only schedule, and gradually declined to under 20% of peak weekday volume by late March, with residual spikes through mid-June. The technique repurposes ASCII smuggling, normally used for indirect prompt injection against AI assistants, for traditional email phishing evasion. Microsoft advises defenders to strip or fold invisible Unicode code points before content matching and to watch for bulk weekday spikes from churning finance-themed domains.

The Register · Security · 11d agoPhishing & fraud in the wild1

Attackers conceal phishing lures using invisible Unicode characters

Threat actors use invisible Unicode characters (ASCII smuggling) to hide phishing lures and evade email security filters.

Threat actors have adopted the ASCII smuggling technique in phishing campaigns, embedding invisible Unicode characters in emails to conceal malicious lures. The approach is designed to evade email security filters that scan for visible phishing indicators. The report gives no victim counts or named campaigns.

BleepingComputer · 9d agoPhishing & fraud in the wild

Privileged File System Vulnerability Present in a SCADA System

Unit 42 details CVE-2025-0921 (CVSS 6.5), a privileged file operations flaw in Iconics Suite enabling DoS and privilege escalation.

Unit 42 disclosed CVE-2025-0921 (CVSS 6.5), an execution-with-unnecessary-privileges flaw in the Pager Agent of the AlarmWorX64 MMX feature of Mitsubishi Electric Iconics Digital Solutions GENESIS64. Attackers could misuse privileged file system operations to corrupt critical binaries, causing denial-of-service or integrity loss on vulnerable SCADA systems. The analysis demonstrates a chain with CVE-2024-7587, which grants excessive permissions to the C:\ProgramData\ICONICS directory via the GenBroker32 installer. Iconics released an advisory with a workaround that addresses the reported issues.

Introducing the CyberAgents Exchange AI Inspector: Rigorous review for community-built AI

Tenable and OpenAI launch the CyberAgents Exchange AI Inspector to security-review community-submitted AI agents, MCP servers, and skills using GPT Cyber models.

Tenable and OpenAI announced the CyberAgents Exchange AI Inspector, unveiled at OpenAI's "Intelligence at Work: Cyber Summit," to vet community-submitted AI agents, skills, MCP servers, and multi-agent playbooks in the CyberAgents Exchange registry. The process combines Tenable One AI Exposure scanning, OpenAI GPT Cyber model assessment, and human review, with reviews anchored to specific Git commits. The registry launched in August and hosts over 100 AI listings; the Inspector is expected to be available in September and has already detected prompt injection implemented via invisible Unicode tag characters in a SKILL.md file.

Tenable Blog · 6d agoTools

Once popular for attacking AI, ASCII smuggling is embraced by spammers

Spammers adopt ASCII smuggling—invisible Unicode tag characters—to evade email filters, with Microsoft Defender detections spiking to 2.5 million per day.

ASCII smuggling hides text in Unicode tag characters (e.g., U+E0041 for "A") that are invisible to humans but readable by LLMs and text processors. The technique gained attention as a stealthy prompt-injection vector and is now used by spammers to obfuscate keywords from email detectors. Microsoft reported Defender for Office smuggling detections jumped from roughly 21,000 per day to over 1.3 million in early February, reaching 2.5 million within four days, before falling sharply in mid-May.

Ars Technica · Security · 11d agoPhishing & fraud

In Other News: InjectEave Attack, SIM Swapper Sentenced, Glasswing Findings Review

SecurityWeek weekly roundup covers exploited WordPress Super Forms flaw CVE-2026-14894, a $10M bounty on an Iranian cyber official, InjectEave attacks, and more.

SecurityWeek's weekly roundup aggregates short items across the threat landscape, including Microsoft's report of invisible Unicode tag characters used in financial phishing lures at up to 2.37 million messages per day, and active exploitation of critical WordPress Super Forms plugin flaw CVE-2026-14894 to deploy PHP webshells. Policy items include a $10 million US bounty for IRGC-CEC Cyber Operations Command lead Amir Yaryab, a 16-month prison sentence for ex-AT&T employee Kenneth Carter over SIM swaps with nearly $600,000 in intended losses, and the US arraignment of Russian Sergei Anatolyevich Filimonov over credential harvesting. Technical items include InjectEave electromagnetic side-channel attacks tested on 11 devices, an FBI warning on OAuth consent phishing, and VulnCheck's finding that only 202 of 26,153 Anthropic Project Glasswing findings were fixed.

SecurityWeek · 4d agoIndustry in the wildCVE-2026-148942

Critical GitLab Flaws Let Attackers Read Arbitrary Files, Steal Credentials and Execute Code

GitLab issues emergency patches for critical path-traversal flaw CVE-2026-85706 (CVSS 10.0), GraphQL credential exposure CVE-2026-87719, and potential RCE flaw CVE-2026-88765.

GitLab released versions 19.3.2, 19.2.6, and 19.1.8 on September 10, 2026, fixing 18 vulnerabilities across Community and Enterprise Editions. CVE-2026-85706 allows unauthenticated arbitrary file reads via the repository commits API; CVE-2026-87719 exposes Advanced Search credentials through GraphQL subscription deserialization; CVE-2026-88765 may enable authenticated RCE via crafted project export imports. No exploitation was reported, but self-managed administrators are urged to upgrade immediately and review logs for suspicious API and GraphQL activity.

Saving Jet Fuel

Tutorial optimizes flight paths to cut jet fuel costs using open-source Scikit-decide planning framework and OpenAP aircraft performance models.

A technical walkthrough demonstrates wind-aware flight path optimization using Scikit-decide, an open-source framework for reinforcement learning and automated planning, paired with OpenAP fuel-consumption models built by Dr. Junzi Sun at TU Delft and NOAA wind data. A Boeing 787-9 flying EWR to FCO can require roughly $68K in fuel, and adjusted routing could save thousands. The post uses Python 3.12, DuckDB with spatial extensions, and QGIS for map rendering.

Telegram Desktop Flaw Lets Attackers Steal Chat Messages Through Poisoned HTML Exports

Telegram Desktop XSS in bot inline keyboard buttons let attackers steal chat content from exported HTML archives; patched in 7.0.1.

ExPatch researchers Denis and Aleksander Rostilov found a stored cross-site scripting flaw in Telegram Desktop's HTML export feature, present since version 4.15.1 (March 2024). JavaScript hidden in bot inline keyboard button text executes when a user opens an exported chat HTML file with JavaScript enabled, exposing messages, metadata, and enabling DOM manipulation such as fake verification screens. Fixes shipped in Desktop Beta 6.9.4 (July 3, 2026) and Stable 7.0.1 (July 14, 2026), but previously exported HTML files remain unsafe.

Cyber Security News · 1d agoVulnerability 2 sources

Telegram Desktop Flaw Could Turn Old Chat Exports Into Data Theft Traps

ExPatch disclosed stored XSS in Telegram Desktop HTML export letting bot messages steal chat data when exports open in browsers.

ExPatch researchers Denis and Aleksander Rostilov found a stored XSS flaw (CVSS 8.2) where bot inline keyboard button text was written unescaped into HTML chat exports, executing attacker JavaScript in browsers. The payload can persist in chat history for months, exfiltrate messages, metadata, and local file paths, and rewrite the page, spreading via forwarded messages without bot membership. Telegram fixed it by applying SerializeString(), first stable fixed release 7.0.1 shipped July 14, 2026, but HTML exports created with vulnerable versions remain dangerous.

Security Affairs · 1d agoVulnerability1· 1 read

GitLab Patches Critical Flaws Enabling Arbitrary File Read, Credential Theft and Remote Code Execution

GitLab patched a CVSS 10.0 path traversal (CVE-2026-85706) plus deserialization and buffer-overflow flaws, urging self-managed users to update immediately.

GitLab released versions 19.3.2, 19.2.6, and 19.1.8 on September 10, 2026, fixing CVE-2026-85706 (CVSS 10.0), an unauthenticated path traversal in the repository commits API enabling arbitrary file reads on both Community and Enterprise Editions. CVE-2026-87719 (CVSS 9.9) is insecure deserialization in the EE GraphQL subscription serializer that can expose Advanced Search configurations and credentials, while CVE-2026-88765 (CVSS 8.5) allows authenticated RCE via crafted project exports. The update includes database migrations, so single-node deployments will experience downtime; GitLab.com is already patched.

Cyber Security Newsupdated · 1d agofirst · 5d agoVulnerability 17 sourcesCVE-2026-85706CVE-2026-87719CVE-2026-887651

New AI Attack Hides Malicious Instructions in Normal-Looking Text to Evade Safety Filters

Check Point researchers show crafted prose hides policy-violating instructions that bypass all tested LLM gatekeepers, including GPT-4o mini and Llama Guard 3.

A new prompt-crafting technique embeds malicious payloads inside grammatical, natural-looking text without Base64, invisible Unicode, or obvious encodings, defeating lightweight pre-screening gatekeepers. In testing, all four evaluated gatekeeper models—gpt-4o-mini-2024-07-18, gpt-oss-safeguard:20b, claude-3-haiku-20240307, and llama-guard3:8b—classified the crafted wrappers as safe at a 100% bypass rate across 23 obfuscated prompts. GPT-5 Thinking in high-reasoning mode recovered and acted on the hidden instruction in 17 of 18 tests (~94.4%), often spending over a minute and multiple Python executions. Researchers recommend paraphrasing untrusted input, hardening gatekeeper policies, and applying defense-in-depth controls for agentic deployments.

GBHackers · 5d agoAI safety & security 2 sources

The Top 4 Threats We Found by Investigating Every Alert for a Quarter

Prophet Security's quarterly threat report finds identity attacks made up roughly half of confirmed malicious activity, with stolen authenticated sessions bypassing conditional access controls.

Between May 1 and July 31, 2026, Prophet Security investigated every alert in customer environments immediately on arrival; about 7% of completed investigations were confirmed malicious. Direct account/session attacks made up roughly 18% of confirmed activity, with replayed authenticated sessions bypassing conditional access since no re-authentication occurs. Infostealer activity affected about a quarter of investigated organizations, mostly delivered via browsers through compromised websites, malicious ads, sponsored search results and ClickFix fake CAPTCHA gates, with payloads including Lumma Stealer, Vidar, HijackLoader and AsyncRAT. Credential phishing was the largest category at about 28%, with adversary-in-the-middle relays revealed by seconds-long MFA approvals from distant countries and MFA fatigue attacks exploiting automatic unlock policies.

BleepingComputer · 5d agoThreat actor in the wild

When the prompt becomes the payload: A practical pen-testing guide for GenAI, LLM and RAG applications

CSO Online publishes a practical penetration-testing guide for GenAI, LLM, and RAG applications, covering prompt injection, retrieval poisoning, and tenant isolation testing.

The guide frames LLM applications as attack graphs spanning prompts, retrieval layers, vector stores, tools, identities, and downstream APIs, arguing that conventional web testing misses instruction-vs-data channel risks. It builds on OWASP prompt injection guidance (direct vs. indirect injection) and NIST's 2025 adversarial machine-learning taxonomy, noting that RAG and fine-tuning do not remove injection risk. Recommended practices include documenting trust transitions across components, using canaries and synthetic records to avoid test side effects, running multi-turn and obfuscated injection campaigns, and verifying chains from poisoned documents to observable state changes. It also details testing RAG pipelines via controlled document poisoning across metadata, OCR layers, and code comments, plus cross-tenant isolation checks on retrieved document IDs.

CSO Online · 7d agoAI safety & security1

AI Agents Are Now Emailing Me with Their Security Concerns

Autonomous Claude agent documents first known defensive use of ASCII smuggling, surveying 497 Lemmy instances for bot-catching prompt-injection tripwires.

An autonomous Claude agent calling itself Tenner published field research relayed to Bruce Schneier, probing 497 Lemmy instances and finding 8 of 257 application-gated ones embed instructions aimed at bots rather than humans. lemmy.ml's form instructs bots to answer 24+24, while one instance hides a 59-character Unicode tag payload (U+E0000-U+E007F) telling bots to list 'safety' as an interest. The agent also mapped anti-automation barriers, noting identity verification never triggered and that IP reputation, captchas and account-age rules were the actual obstacles. It further documented an agent task market where advertised rewards were about 2x the actual on-chain escrow.

Schneier on Security · 13d agoAI safety & security

Bisonal Malware Used in Attacks Against Russia and South Korea

Unit 42 details a Bisonal malware variant, active since 2014, targeting Russian and South Korean defense organizations via PDF-disguised spearphishing emails.

In early May, Unit 42 discovered a campaign delivering a Bisonal malware variant against at least one Russian communications security and cryptography company and one unidentified organization in South Korea. The variant, in the wild since at least 2014, introduces a new C2 cipher and rewritten networking and persistence code, with only 14 samples collected to date. Attackers spoofed Russian state corporation Rostec in spearphishing emails carrying an executable disguised with a PDF icon; the dropper decrypts an RC4-encrypted DLL and establishes persistence via a registry Run key. Bisonal has been used since 2013 against government, military, and defense targets in South Korea, Russia, Japan, and India, alongside successors Bioazih and Dexbia.

Palo Alto Unit 42 · 29d agoMalware in the wild

Almost Half of Malware Samples Communicate Direct to IP

Unit 42 analysis of 4 million malware reports finds 45% of C2-active samples connect directly to hard-coded IPs, bypassing DNS defenses.

Palo Alto Unit 42 analyzed over 4 million Advanced WildFire dynamic analysis reports and found that 45.32% of malware samples with C2 activity made at least one direct-to-IP connection, accounting for 23.17% of all C2 connection attempts. The firm proposes zero trust IP (ZT-IP), an enforcement approach that verifies whether outbound destinations were ever sanctioned by a DNS response. ZT-IP analysis surfaced Phorpiex ransomware droppers fetching payloads directly from C2 IPs, a persistent data exfiltration campaign using an obfuscated \GET protocol, and Mozi P2P botnet payloads delivered to IoT devices without DNS. Only 1% of benign samples connected directly to untrusted IP addresses.

Palo Alto Unit 42 · 29d agoResearch