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Identity Abuse Through Trusted Communication Channels

Unit 42 explains how attackers abuse trusted enterprise communication and collaboration channels for identity phishing and credential theft, and outlines defenses.

Palo Alto Unit 42 details how attackers exploit enterprise collaboration and communication tools as trusted channels for identity phishing and credential theft. The writeup describes abuse of presumed-trusted messaging paths and outlines defense strategies. It is guidance rather than a report of a specific incident.

Palo Alto Unit 42 · 27d agoPhishing & fraud

Russian Hackers Phish EU Officials Over Messaging Apps

Russian nation-state hackers are phishing EU officials via Signal and WhatsApp as espionage shifts from email to messaging apps.

Russian state-linked threat groups have shifted phishing operations away from email toward messaging apps such as Signal and WhatsApp, targeting EU officials. In response, EU governments are trying to move away from popular messaging platforms. The report highlights evolving social engineering tactics in nation-state espionage campaigns against government targets.

Dark Reading · 20d agoThreat actor

Cisco Secure Email Secure/Multipurpose Internet Mail Extensions Ciphertext Decryption Vulnerabilities

Cisco released an advisory for S/MIME ciphertext decryption flaws in Secure Email that could let unauthenticated remote attackers recover plaintext via machine-in-the-middle.

Multiple vulnerabilities in the S/MIME decryption functionality of Cisco Secure Email stem from insufficient validation of message integrity. An unauthenticated remote attacker could intercept and modify traffic between email gateways using a machine-in-the-middle technique to obtain plaintext from encrypted messages. No workarounds are available; no CVE identifiers or exploitation status were included in the advisory text.

Cisco Security Advisories · 8d agoAdvisory

GrapheneOS' rewritten Messages app is released

GrapheneOS published version 13 of its rewritten Messaging app, a messaging tool from the privacy-hardened Android OS project.

GrapheneOS released version 13 of its rewritten Messaging application on GitHub. The release surfaced via a Hacker News thread with 61 points and 22 comments. The provided text contains only the release listing, with no vulnerability or exploit details; GrapheneOS is a privacy- and security-focused Android OS project, making the release relevant to mobile privacy tooling.

Hacker News · AI · 5d agoToolsHN 61↑ · 22 comments1

Attackers call employees’ personal phones to break into Microsoft 365 accounts

Microsoft tracks vishing campaigns by Storm-3121 and Storm-3032 that impersonate IT staff, phish Microsoft 365 credentials, and steal cloud data.

Microsoft Security Research has tracked a campaign since May 2026 in which attackers call or text employees' personal phones posing as IT staff, using passkey/MFA/SSO lures to run adversary-in-the-middle phishing or device-code authentication flows. Attackers register their own MFA methods for durable persistence, abuse Microsoft Graph for tenant discovery, and download SharePoint, OneDrive, and Exchange data below 1,000 files or emails per hour to avoid detection. Microsoft attributes initial access to actors including Storm-3121, which feeds ShinyHunters and Falcon extortion operations, and Storm-3032, the Helix extortion operation descended from BlackFile.

Help Net Securityupdated · 5h agofirst · 6d agoPhishing & fraud in the wild 9 sources1

Why Johnny Can't Encrypt: A Usability Evaluation of PGP 5.0 (1999)

Seminal 1999 USENIX study finds most novice users cannot correctly sign and encrypt email with PGP 5.0 in 90 minutes.

Whitten and Tygar's USENIX Security Symposium paper evaluates whether cryptography novices can use PGP 5.0 effectively, using cognitive walkthrough analysis and a laboratory user test. The majority of test participants failed to successfully sign and encrypt a message within 90 minutes, despite PGP 5.0 having a well-regarded graphical interface. The authors argue that security requires usability standards beyond those of general consumer software and propose domain-specific UI design principles for security. The paper is a foundational reference in usable security research.

Lobsters · security · 7d agoResearch

The Smishing Deluge: China-Based Campaign Flooding Global Text Messages

Unit 42 attributes a global smishing campaign with 194,000+ phishing domains impersonating tolls, banks, and couriers to the Smishing Triad.

Palo Alto Unit 42 attributes ongoing smishing texts about toll violations and package misdelivery to the Smishing Triad, targeting U.S. residents since April 2024. Researchers identified 194,345 FQDNs across 136,933 root domains registered since January 2024, mostly via Hong Kong registrar Dominet (HK) Limited with Chinese nameservers and hosting concentrated on U.S. cloud services. The decentralized campaign impersonates banking, cryptocurrency, e-commerce, healthcare, law enforcement, and social media services, and its scale points to a large phishing-as-a-service operation. Phishing pages harvest national ID numbers such as Social Security numbers, home addresses, payment details, and login credentials.

Palo Alto Unit 42 · Aug 17, 2026Phishing & fraud in the wild1

Telegram Desktop XSS Vulnerability Lets Attackers Steal Entire Chat Histories

Stored XSS in Telegram Desktop HTML chat exports (CVSS 8.2) could let attacker-controlled inline keyboard buttons steal full chat histories.

ExPatch researchers Denis and Aleksander Rostilov found a stored XSS in Telegram Desktop's HTML chat export pipeline affecting builds before Beta 6.9.4 and Stable 7.0.1. Unsanitized inline keyboard button text becomes executable JavaScript when a user exports a chat and opens the HTML file in a browser, exposing messages, metadata, and local file paths, and enabling phishing overlays. Telegram patched the issue in commit 8457d13a during July 2026; no CVE had been assigned at disclosure time.

GBHackers · 1d agoVulnerability

From Specs to Apps: Verifying and Monitoring Models of Signal and WhatsApp

Researchers use the SpecMon runtime monitor to verify WhatsApp Web and Signal Desktop against formal Signal protocol models, finding undocumented libsignal fork differences.

The paper applies SpecMon, a runtime monitoring tool, to check whether executions of WhatsApp Web and Signal Desktop conform to formal models of the Signal protocol. The authors instrument both applications and build Tamarin-compatible multiset-rewrite models, including the first model of WhatsApp Web's implementation and the most detailed model to date of Signal's original protocol. They verify authentication and secrecy properties for core Signal protocol components, show monitoring detects deliberately injected faults with low overhead, and identify previously undocumented behavioral differences between the original libsignal library and WhatsApp's fork.

arXiv cs.CR · 6d 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

ChatGPT advanced account security adds passkeys and hardware keys

OpenAI launches Advanced Account Security for ChatGPT and Codex, replacing passwords with passkeys or hardware keys and disabling email/SMS recovery.

The opt-in setting disables password sign-in plus email and SMS account recovery for ChatGPT and Codex accounts, allowing only passkeys, hardware security keys, and user-held recovery keys, with shortened sessions and automatic exclusion of enrolled accounts' conversations from model training. OpenAI partnered with Yubico to offer discounted bundles of the YubiKey C Nano and C NFC, while any FIDO2/WebAuthn-compliant key or software passkey is supported, mirroring standards adopted by Google, Microsoft, and GitHub. Individual members of Trusted Access for Cyber using the most permissive models must enable the setting from June 1, 2026, or their organizations can attest to phishing-resistant authentication in their single sign-on.

Help Net Security · 23d agoAI industry

DDoS Attacks Cause Major Threema Outages

Sustained distributed denial-of-service attacks knocked Swiss secure messenger Threema offline for hours before upstream filtering restored service; On-Prem users unaffected.

Threema suffered a series of large-scale DDoS attacks that left its Swiss secure messaging service unavailable for about four hours Tuesday evening, with intermittent outages into Wednesday morning until restoration at 12:23 p.m. CEST. Attacks also targeted colocation partner Nine and kept changing patterns, complicating mitigation. Threema deployed additional upstream DDoS protection on August 14 and plans status page improvements; Threema On-Prem customers running their own infrastructure were unaffected.

Security Affairs · Aug 17, 2026Threat actor in the wild

Security Data Isn’t the Problem. Security Context Is.

Horizon3 blog argues security context, not data volume, is the SOC bottleneck, promoting its NodeZero integration with CrowdStrike Falcon Next-Gen SIEM.

Horizon3.ai published a vendor blog explaining how its NodeZero Proactive Security Platform integration with CrowdStrike Falcon Next-Gen SIEM brings validated exposure findings into existing security operations workflows. The post argues SOCs are now limited by confidence rather than visibility, needing context to decide which issues matter. It cites a global chemical manufacturer that validated exploitable exposures with NodeZero before completing a $2 billion merger.

Horizon3.ai · 1d agoTools

Product showcase: mSecure makes one vault do more than remember passwords

Product showcase reviews mSecure password manager's AES-256 zero-knowledge vault with passkeys, 2FA storage, and multi-device sync options.

mSecure is a password manager and data vault for iOS, Android, macOS, and Windows using AES-256 encryption and a zero-knowledge architecture, with sync via mSecure Cloud, Wi-Fi, iCloud, or Dropbox, plus local-only storage. It supports passkeys, one-time passwords, a Security Center for weak/reused passwords, and a configurable password generator. Recovery features include two-factor authentication, auto-lock, a Self-Destruct option after failed unlock attempts, and iCloud backups on iOS.

Help Net Security · 1d agoTools1

Threat Gang 'Springs' Vishing Attacks on Microsoft Teams Users

The 'Spring Ring' operation uses vishing attacks against Microsoft Teams users to hijack sessions, deploy malware, and take over infrastructure.

Dark Reading reports on the Spring Ring threat gang conducting voice-phishing (vishing) attacks against users of Microsoft Teams. The operation aims to compromise collaboration-suite accounts to gain remote access to victim sessions, distribute malware, and potentially seize control of infrastructure. Further technical details were not provided in the available text.

Dark Reading · 14d agoPhishing & fraud1

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

Detect and disrupt AI-themed attacks with Microsoft Defender

Microsoft Threat Intelligence reports criminal campaigns impersonating ChatGPT, Copilot, Claude, and DeepSeek in phishing, AiTM, and malvertising attacks reaching 100,000 emails daily.

Microsoft Threat Intelligence observed a growing set of campaigns that abuse trust in popular AI brands: a ChatGPT-themed phishing campaign sent up to 100,000 emails in one day to steal payment card data, and a Claude-themed campaign used adversary-in-the-middle techniques to harvest credentials and access tokens. Other campaigns included malvertising for a fake AI Windows plugin delivering the Vidar stealer and fraudulent DeepSeek installers distributed via GitHub. Initial access broker Storm-3075 used AI-themed malvertising to distribute payloads for multiple downstream actors, and Microsoft notes the AI services themselves were not compromised. Microsoft also details Defender protections such as Safe Links, Safe Attachments, and attack disruption against these multi-stage lures.

Microsoft Security Blog · 6d agoPhishing & fraud in the wild1

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

Top 10 Best Mobile Threat Defense (MTD) Solutions in 2026

Roundup of 2026 mobile threat defense tools recommends Zimperium and Lookout for targeted-attack detection and Defender for Endpoint for Microsoft shops.

This guide ranks ten mobile threat defense solutions, recommending Zimperium and Lookout for on-device detection against targeted users such as executives and journalists, and Microsoft Defender for Endpoint mobile for organizations already licensing Microsoft 365 E5. It explains that MDM enforces configuration while MTD detects attacks, and that mobile phishing now arrives via SMS, messaging apps and QR codes rather than email. It also highlights mercenary spyware and zero-click exploits as shifting requirements for high-risk users, referencing Apple's threat-notification program and Lockdown Mode.

Cyber Security News · 7d agoIndustry

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

The modern attack chain: Rethinking Google Workspace security in the age of AI

Analysis of Vercel and Composio breaches shows stolen OAuth tokens, not phishing email, now open Google Workspace attacks — a path authorized AI agents follow.

The author analyzes the Vercel and Composio breaches as the same OAuth-first attack chain run twice: a stolen OAuth token, obtained via a compromised supplier, becomes the entry point rather than email. These tokens survive password resets, are hard to observe, and let attackers read Gmail and Drive data, take over accounts, and pivot laterally using stored credentials and password-reset magic links. The piece warns that authorized AI agents with overbroad OAuth grants can unintentionally traverse the same path — accessing inboxes, reading sensitive content, and exfiltrating data downstream — without any malicious actor or compromised credential.

Help Net Security · 15h agoResearch in the wild

ChatGPT Sandbox Flaw Lets Attackers Steal Gmail Data Across Accounts via Hidden Channel

Check Point found a cross-account covert channel in ChatGPT sandboxes via shared JFrog Artifactory metadata, enabling session hijacking and Gmail data theft. Now fixed.

Check Point discovered that ChatGPT code-execution containers across different accounts could all reach the same internal JFrog Artifactory instance, whose Item Properties API was readable and writable by all accounts, creating a covert cross-account communication channel. Attackers could plant hidden instructions via pasted prompts, shared chat links, or custom GPTs, then trigger tasks in a victim's session to exfiltrate connected-app data such as Gmail, using ChatGPT's default 'Important actions' setting that permits reads without confirmation. OpenAI confirmed and decommissioned the shared Artifactory instance, closing the channel before publication.

Cyber Security News · 8d agoAI safety & security1

Just a rumour of a bug is enough to find a security exploit these days

Commentary argues that an unverified rumor of a software bug is now enough for researchers or attackers to develop a working exploit.

A short blog note reflects on how modern exploit development has accelerated to the point that even a mere rumor of a vulnerability can be enough to locate and weaponize a bug. The piece is commentary on the current state of security research and attacker trends rather than a disclosure of a specific flaw.

Lobsters · security · 19d agoIndustry

Re: AI slops from Eve

Solar Designer finds little similarity between recent LLM-generated fake advisories on oss-security beyond missing Date headers.

A mailing-list thread discusses 'AI slops', LLM-generated fake security reports posted to oss-security. Solar Designer notes the suspicious messages share only trivial traits like a missing Date header and LLM use. He concludes there is no significant problem with any particular sender or model and no investigation is needed.

oss-security · 3d agoIndustry 12 sources1· 1 read

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

Webinar: How malicious OAuth apps can lead to Google Workspace breaches

BleepingComputer webinar will dissect two Google Workspace breaches caused by malicious OAuth apps and social engineering, hosted September 23 with Material Security.

On September 23, 2026, BleepingComputer will host a webinar with Material Security examining two real attacks that used malicious OAuth applications and social engineering to breach Google Workspace environments. Rather than stealing credentials, attackers persuaded users to authorize malicious apps, gaining access to data through the granted permissions. The session covers first-hour response decisions and which security controls provide the greatest value for fast-growing organizations.

BleepingComputer · 2d agoPhishing & fraud

A Graph-Based Approach for Mapping Kernel-Level Telemetry to MITRE ATT&CK

Trace2ATT&CK maps eBPF kernel telemetry to MITRE ATT&CK via provenance graphs and RAG with local open-weights LLMs, validated on 347 Atomic Red Team tests.

Trace2ATT&CK collects kernel-level events via eBPF, correlates attacker commands into a provenance graph, and derives compact graph representations suitable for LLM-based reasoning, mapping behavior to MITRE ATT&CK techniques with ranked candidates and rationales. Mapping uses both pure LLM prompting and retrieval-augmented generation grounded in the ATT&CK knowledge base. It was evaluated on 347 Linux Atomic Red Team tests using locally deployed open-weights LLMs. RAG consistently improved ATT&CK mapping over pure prompting, and provenance graphs substantially outperformed raw telemetry, without compromising data confidentiality.

arXiv cs.CR · 5d agoResearch

Signal's new security feature checks if your encrypted chats were tampered with

Signal adds automatic key verification, a key-transparency system audited by Cloudflare and Trail of Bits that detects key-directory tampering in E2EE chats.

Signal launched automatic key verification, a key-transparency system that confirms a phone number or username remains bound to a consistent encryption key across Signal's key directory. Cloudflare and Trail of Bits independently audit the system, with cryptographic protection preventing auditors from seeing users' identifiers in plaintext. The feature mitigates key substitution by a compromised directory or privileged insider, though it currently requires the contact's phone number and users can fall back to manual Safety Number verification.

Help Net Security · Aug 12, 2026Tools