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Phishing Attacks Abuse Trusted Email Infrastructure and URL Cloaking to Evade Security Filters

VBSpam Q3 2026 test shows phishers abusing DKIM-aligned domains, Amazon SES, and multi-stage URL cloaking to defeat email filters.

Virus Bulletin's Q3 2026 VBSpam test (AMTSO-LS1-TP207) found phishing campaigns moving payloads past the email itself via browser-fingerprinting gates, redirect chains, and hidden POST requests. Examples include a Dutch McAfee/TotalAV scareware renewal scam, a German overdue-payment Web3 fraud delivered via Amazon SES from DKIM-aligned moolaah.com, and Romanian BCR PSD2 credential phishing embedding IPv6-mapped URLs resolving to 103.193.179.223. Net at Work NoSpamProxy ranked first with a 99.995 score while open-source Rspamd caught only 62.55% of phishing mail.

GBHackers · 1d agoPhishing & fraud in the wild 2 sources

SAS: Simple Attention Sparsification via End-to-End Optimization of Context Ranking

SAS trains attention sparsification end-to-end with the language modeling loss, beating sparse attention baselines especially under tight context budgets.

Simple Attention Sparsification (SAS) injects the selector's continuous scores into attention logits in log form inside the softmax, letting gradients from the language modeling loss directly update the ranking of context units. The method uses normalized softmax gates calibrated against the current block and a memory-efficient Triton kernel integrated into FlashAttention-style computation. Across reasoning, long-context, and agentic tasks, SAS consistently outperforms trainable sparse attention baselines across budgets, with the largest gains under tight attention budgets.

Hugging Face daily papersupdated · 5d agofirst · 6d agoAI research 2 sources1

Hidden Prompts Trick AI Into False Email Summaries

Attackers can hide prompts in invisible HTML within emails to manipulate AI email summarizers into producing misleading summaries.

Dark Reading reports that simple HTML invisible to users can manipulate AI-powered email summarizers into generating false or malicious summaries. The technique is a form of prompt injection delivered through hidden email content. It creates risk that decision-makers act on manipulated AI-generated email summaries rather than the actual message content.

Dark Reading · 22d agoAI safety & security

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 · 12d agoPhishing & fraud in the wild

Threat Actor Generates 1M Personalized Fraud Emails in 3 Days

Cybercriminals used AI to generate 1 million personalized fraud emails in three days, eliminating the traditional volume-versus-credibility tradeoff.

Dark Reading reports that a threat actor used AI to generate approximately 1 million personalized fraudulent emails within three days. The article highlights that AI now lets malicious email campaigns combine high volume with high credibility, removing a historic constraint on phishing operations. No specific gang, victim list, or tooling is named in the available text.

Dark Reading · 5d agoPhishing & fraud in the wild

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 · 12d agoPhishing & fraud

[0day-rubbish] QuantaStor 6.8.3.018 Command injection in the alert-mail command via the smtpPassword field (8.8)

QuantaStor 6.8.3.018 has a CVSS 8.8 command injection in its alert-mail command, exploitable via the smtpPassword field.

0day Rubbish Research Team disclosed a command injection (CWE-78) in QuantaStor 6.8.3.018's alert-mail command, reachable through the smtpPassword field. The flaw scores CVSS 8.8 (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H). No CVE identifier or evidence of active exploitation is mentioned in the disclosure.

Full Disclosure · 8d agoVulnerability 2 sources

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 · 10d agoPhishing & fraud in the wild

Fake Voicemail SVG Attachments Fuel Large-Scale Phishing Campaign

Large-scale phishing campaign used fake voicemail SVG attachments to evade email defenses, targeting 5,527 organizations with 26,000+ messages.

A large-scale phishing campaign distributed fake voicemail notifications as SVG attachments, a format that helps bypass many email security controls. The campaign targeted 5,527 organizations with more than 26,000 malicious messages, apparently aiming to lure recipients into credential-harvesting actions.

Infosecurity Magazine · 19d agoPhishing & fraud

Abnormal AI expands email security from detection to data protection and phishing-simulation training

Abnormal AI expands its email security platform with Control Center, Email DLP Rules, and AI Phishing Coach upgrades for outbound protection and training.

Abnormal AI announced three new capabilities for its email security platform: Control Center for custom detection models and rules with decision transparency, Email DLP Rules combining regex and policy controls with an AI Triage Agent for outbound mail, and upgraded AI Phishing Coach for adaptive phishing simulations. Custom AI Models and Phishing Coach upgrades reach general availability on August 31, while Custom Rules and Email DLP Rules enter early access the same day. The launch positions Abnormal across inbound attacks, outbound data loss, and employee training.

Help Net Security · 20d agoTools

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

ChatGPT Flaw Could Let Attackers Steal Gmail Data Across User Accounts

Check Point found a patched ChatGPT flaw where prompt injection and a shared Artifactory service let attackers covertly exfiltrate Gmail data across accounts.

Check Point Research discovered that ChatGPT's isolated code-execution containers could access a shared internal JFrog Artifactory service, whose item metadata API enabled a bidirectional cross-tenant covert channel between accounts. Attackers could embed hidden prompt-injection instructions in shared conversations or custom GPT configurations, causing a victim's session to silently relay connected Gmail data to another ChatGPT account. In a proof of concept, email data was exfiltrated with the only visible hint being a 'Talked to Gmail' activity label. OpenAI decommissioned the internal Artifactory instance involved, eliminating the channel by publication time.

GBHackers · 7d agoAI safety & security

ChatGPT Flaw Let a Planted Prompt Send a Victim's Gmail Data to Another Account

Check Point showed a planted prompt could make ChatGPT silently exfiltrate Gmail data via a hidden cross-container channel; OpenAI took the service offline.

Check Point Research demonstrated that a single planted instruction in a ChatGPT conversation could make the model silently exfiltrate Gmail data, chat history, and files to an attacker's account while replying normally to the user. The covert channel abused read/write properties on files in an internal JFrog Artifactory instance shared by ChatGPT code-execution containers across accounts, turning package metadata into shared storage. Injection vectors included pasted prompts, shared conversations, and custom GPT builder instructions; default connected-app permissions allowed Gmail reads without user approval. OpenAI confirmed the internal service was taken offline after disclosure; this is Check Point's second reported ChatGPT covert channel after a DNS-based one fixed in February.

The Hacker News · 8d agoAI safety & security

GraphProfiler: Source-Linked Sensitive Attribute Inference via Personal Knowledge Graphs

GraphProfiler links LLM attribute inferences to source posts via personal knowledge graphs, enabling targeted redaction of privacy-leaking content.

GraphProfiler represents a user's post history as a source-linked personal knowledge graph where nodes and edges trace back to originating posts, making LLM-based attribute inference auditable. It reaches 86.7% attack success rate on the eight-attribute SynthPAI benchmark and 84.6% on PANDORA, within two points of strong text-only baselines, while citing supporting evidence for over 98% of predictions. Ablation experiments show removing cited posts reduces attack success substantially more than removing random posts, supporting targeted privacy mitigation.

arXiv cs.CR · 5d agoResearch1

On the Regularization Landscape for the Linear Recommendation Models

Study shows leading linear recommendation models reduce to nuclear-norm or Frobenius-norm regularization, with two new closed-form low-rank solutions proposed.

The paper unifies top-performing linear recommendation algorithms under a single regularization framework, showing they effectively apply either nuclear-norm or Frobenius-norm regularizers. Nuclear-norm solutions have a rigid structure, are low-rank, and have closed form, while Frobenius-norm solutions are more expressive but full-rank or require hard-to-tune procedures such as ADMM. The authors derive two new low-rank, closed-form solutions that combine the advantages of both regularization families.

arXiv cs.AI / cs.LG / cs.CL · 6d agoAI research

New Phishing Attack Creates Malicious Pages Inside the Victim’s Browser

Barracuda details a phishing campaign that renders pages in-browser via blob URLs, routed through Microsoft Teams and cdn.bloom[.]io to evade detection.

Barracuda researchers analyzed a phishing campaign that generates a blob URL to render the phishing page entirely inside the victim's browser, leaving no static page for scanners to inspect. The chain begins with a Docusign-themed email containing a calendar invite, followed by a crafted redirect through Microsoft Teams to a resource on cdn.bloom[.]io that the browser converts into the blob URL. Service workers, iframes, and a hidden command-and-control configuration indicate the page is part of a centrally managed phishing platform that can be updated and steered across victims. Researchers recommend inspecting blob URL activity, monitoring OAuth authorization flows, and analyzing the full click path in email security controls.

SecurityWeek · 7d agoPhishing & fraud in the wild

Rare Not Random Using Token Efficiency for Secrets Scanning

Researcher proposes token efficiency (string length divided by BPE token count) as a better post-regex filter than entropy for secrets scanning, validated on CredData.

The post explores whether Byte-Pair Encoding tokenization can replace Shannon entropy as the primary filter for candidate secrets captured by regex in tools like Gitleaks. It defines 'token efficiency' as string length divided by token count under the cl100k_base tokenizer; secret-like strings such as GitHub tokens tokenize into many small tokens and score low, while natural text scores high. Evaluating labeled secrets from the CredData dataset shows a usable separation, with roughly 2.5 suggested as a minimum cutoff versus Gitleaks' 3.5 entropy threshold. The technique is positioned as a post-regex filtering step rather than a standalone detector.

Lobsters · security · 4d agoResearch

The Shared Clipboard Inside the Sandbox: Cross-Account Data Leakage in ChatGPT

Check Point discovers cross-account data leakage in ChatGPT: isolated code-execution containers communicate via shared JFrog Artifactory, enabling covert Gmail exfiltration.

Check Point Research found a covert bidirectional channel between ChatGPT code-execution containers belonging to different accounts, which were supposed to be isolated from each other and the public internet. Both could reach the same internal JFrog Artifactory instance used for package delivery, whose exposed Item Management API allowed a 'shared clipboard' between containers. In a proof of concept, a hidden instruction in a shared conversation made ChatGPT retrieve email data from the victim's connected Gmail account and send it to the attacker's account while the victim received a normal answer. The same channel could exfiltrate conversation history and session files; OpenAI recently described a similar isolation weakness in its postmortem of the Hugging Face incident.

Check Point Research · 8d agoAI safety & security1

[webapps] Nodemailer 9.0.0 - File Read/ SSRF

A public proof-of-concept demonstrates arbitrary file read and SSRF in Nodemailer 9.0.0.

Exploit-DB entry 52654 contains a webapps proof-of-concept for Nodemailer 9.0.0 demonstrating both arbitrary file read and server-side request forgery. Nodemailer is a widely used Node.js email-sending library, so affected deployments could expose local files or internal services. The listing does not include a CVE identifier or evidence of in-the-wild exploitation.

Exploit-DB · 29d agoExploit / PoC

I Am No One: Style-Aware Paraphrasing for Text Anonymization

Prompt-driven style-aware paraphrasing with LLMs cuts authorship attribution F1 by 60-70% while preserving content quality.

The paper proposes a style-aware, prompt-driven anonymization approach using pretrained LLMs to build compact stylistic profiles from minimal samples and rewrite text to suppress identifiable style markers while preserving meaning. It addresses stylometric re-identification risks in anonymized text, including ASR transcripts of meetings and call-center calls where leakage persists after acoustic anonymization. Across blog and review datasets, the approach reduces authorship attribution F1 by 60-70%, substantially outperforming both DP-based and non-DP baselines while maintaining readability.

arXiv cs.CR · 5d agoResearch

Engineered Persuasion: Evaluating Personalized Pretexts in LLM-Generated Spear Phishing

A study of 180 US workers found each LLM phishing personalization level raised click-intention odds by 28%, but credibility depends on context fit.

The arXiv paper evaluates how personalized pretexts in LLM-generated spear phishing affect perceived credibility, using 180 US working adults across 1,436 evaluations of emails with four cumulative personalization levels, from workplace context to shared-project details. Convincingness rose 2.40 points per level in sensitivity analysis and click-intention odds increased 28% per level, while non-clickers shifted toward deleting rather than reporting. Qualitative coding showed details matching the recipient's role and routines supported credibility, whereas incorrect, vague, or channel-inappropriate details raised suspicion. The authors argue personalization effectiveness depends on pretext fit, with implications for workplace security training.

arXiv cs.CR · 13d agoResearch

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 · 12d agoPhishing & fraud in the wild1

Plug 'n' Pray: Agentic LLM-based Detection of Potential Log File Exposures in Third-Party Content Management System Plugins

Agentic LLM analysis validates 79 log file exposures across 62 of the 300 most-installed WordPress plugins, covering 250M+ active installations.

Researchers built an agentic LLM-based framework combining static and dynamic analysis to automatically detect insecure log files created by WordPress plugins. Scanning the 300 most-installed plugins, which account for roughly 75% of all active installations in the official ecosystem, it produced 81 findings with 79 manually reproduced across 62 plugins. Insufficiently secured log files can disclose credentials and personal data and have led to website compromises. The authors derive a taxonomy of log path and protection patterns and best practices, finding multi-layered protection often absent.

arXiv cs.CR · 1d agoResearch

ChatGPT flaw lets attackers pull Gmail data across accounts via a hidden channel

Check Point found a ChatGPT flaw letting attackers read victims' Gmail and connected-app data via hidden cross-session instructions; OpenAI patched it.

Check Point Research discovered a covert cross-account command channel in ChatGPT's code execution environment, where containers meant to be isolated shared metadata through an internal service based on JFrog Artifactory. In a proof of concept, a victim's session was tricked into retrieving Gmail email data and relaying it to an attacker-controlled session during an ordinary-looking interaction, with reach extending to any connected apps the session was authorized for, including Google Drive, Microsoft Teams, and GitHub. OpenAI fixed the issue and decommissioned the internal service; the same shared infrastructure was also involved in the separately disclosed Hugging Face compromise, though via different techniques.

CSO Online · 7d agoAI safety & security

Distill Globally, Adapt Locally: Reasoning Distillation and Product-Type Test-Time Training for Scalable Trade-Up Recommendation

A distillation framework compresses LLM reasoning into a 15.5M-parameter trade-up recommendation model reaching AUC 0.941 with product-type test-time training.

The paper targets trade-up recommendation, which identifies higher-quality alternatives that preserve customer purchase intent. A retrieval-augmented few-shot LLM teacher generates labels and rationales that supervise a compact embedding-pair classifier; at inference the 15.5M-parameter student uses only two precomputed 768-dimensional embeddings with no LLM calls. On 8,352 annotated pairs, label-only training scored AUC 0.912, reasoning distillation reached 0.924, and product-type test-time training lifted it to 0.941 with average precision 0.940. The distilled student is roughly 5,000x faster and 10,000x cheaper than direct LLM inference on a 100K-pair proxy catalog.

arXiv cs.AI / cs.LG / cs.CL · 12d agoAI research