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Hackers Exploit Critical Cisco Secure Email Gateway Vulnerability in the Wild to Run Malicious Code

Cisco warns attackers actively exploit zero-day CVE-2026-76461 in Secure Email Gateway, gaining unauthenticated root command execution via crafted emails.

Cisco PSIRT confirmed active in-the-wild exploitation of CVE-2026-76461 throughout September 2026, a zero-day in Secure Email Gateway AsyncOS that lets remote, unauthenticated attackers execute arbitrary commands with root privileges by sending maliciously crafted emails containing injected SQL statements. Physical appliances, virtual deployments, and Cisco Secure Email Cloud instances were affected; Cisco deployed server-side remediations for cloud tenants but on-premises admins must patch themselves. Fixes ship in AsyncOS 16.5.0-780 plus branches 16.0.4-3021 and 15.5.5-0141, and no workarounds exist.

Cyber Security Newsupdated · 8h agofirst · 1d agoExploit / PoC in the wild 17 sourcesCVE-2026-76461

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

Postfix: SMTP smuggling, remote crash, and hardening fixes in 3.11.7 and related legacy releases

Postfix 3.11.7 and legacy releases 3.10.14 and 3.9.15 fix SMTP smuggling, remote crash, and hardening issues.

Wietse Venema announced the Postfix stable release 3.11.7 alongside legacy releases 3.10.14 and 3.9.15. The releases fix SMTP smuggling, a remote crash vulnerability, and include hardening changes in the widely used mail transfer agent. Administrators running Postfix are advised to update to the patched versions.

oss-security · 6d agoVulnerability

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

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

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

[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

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

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

Don't Trust the Super-App: A Case Study of Russia's Max

Researchers show super-apps like Russia's Max can silently capture mini-app UI, storage, network traffic, and authentication, enabling untraceable user impersonation.

The paper challenges the assumption that super-apps are trusted intermediaries, citing WeChat's passive cross-mini-app tracking, Russia's Max's entanglement with state prosecution of online speech, and Iran's Bale operating during a prolonged internet shutdown. Using Max as a case study, the authors demonstrate that a super-app can capture mini-app UI, read and write mini-app local storage, inject arbitrary JavaScript into mini-app runtimes, mediate network traffic, and control authentication context, enabling silent user impersonation without trace. They argue these capabilities are inherent to the super-app architecture and call for mobile OS and app store interventions to close the blind spot.

arXiv cs.CR · 6d agoResearch1

Crypto customers targeted by scammers after email marketing provider breach

Attackers exploited a Brevo SAML SSO flaw to access 138 accounts and phish crypto customers of Trezor, CoinTracking, and BitBox.

An attacker exploited a flaw in Brevo's SAML SSO handling to access 138 customer accounts on September 10; six accounts were used to send phishing emails and contacts were exported from 43 accounts. Crypto firms Trezor, CoinTracking, and BitBox confirmed customers received phishing emails, with Trezor warning roughly 347,000 newsletter subscribers. The Trezor-themed email cited a fabricated STM32 microcontroller entropy bug and urged recipients to enter wallet backups through a malicious link. Exported contact lists could fuel future targeted phishing attacks.

Malwarebytes Labs · 5d agoData breach in the wild 6 sources

Cisco Secure Email Gateway SQL Injection Vulnerability

Unauthenticated SQL injection in Cisco Secure Email Gateway email parsing enables root command execution via crafted messages; patches released.

A vulnerability in email parsing of Cisco AsyncOS for Cisco Secure Email Gateway allows an unauthenticated, remote attacker to execute arbitrary commands with root privileges on the underlying operating system. Insufficient validation in the email parsing logic lets a crafted email containing malicious SQL statements achieve arbitrary SQL execution and root command execution. Cisco has released software updates, and the companion September 2026 hardening advisory states this flaw is actively exploited.

Cisco Security Advisories · 2d agoVulnerability in the wild

Researchers Build WeChat Zero-Click Worm Hijacking Phones via Calls

Calif researchers built WeWorm, a zero-click worm exploiting a WeChat VoIP memory-corruption RCE that Tencent has now patched.

Calif researchers found a memory corruption flaw in WeChat's VoIP stack in July using LLM-assisted analysis and built working exploits within two days, then integrated them into WeWorm, which they call the first zero-click worm spreading through WeChat calls on iOS and Android. A crafted incoming call yields remote code execution with no user interaction, giving full control of the victim's WeChat account; the attacker only needs to be on the victim's friend list, easily achieved by compromising a contact first. Tencent confirmed the bug and shipped patches in WeChat Android 8.0.77 and iOS 8.0.76, and chaining with other OS bugs could yield full device control.

Infosecurity Magazine · 7d agoExploit / PoC

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

Cisco Packaged Contact Center Enterprise and Cisco Unified Contact Center Enterprise Server-Side Request Forgery Vulnerability

Cisco patched an authenticated SSRF flaw in Packaged CCE and Unified CCE that lets credentialed users send arbitrary network requests from affected devices.

A server-side request forgery vulnerability caused by improper input validation of specific HTTP requests affects Cisco Packaged Contact Center Enterprise and Cisco Unified Contact Center Enterprise. An authenticated, remote attacker with valid user credentials can send crafted HTTP requests to make the device issue arbitrary network requests. Cisco has released software updates; no exploitation is reported in the advisory.

Cisco Security Advisories · 28d agoAdvisory

cPanel EmailTrack SQL Injection Flaw Lets Attackers Execute Code as Root

cPanel disclosed CVE-2026-67401, an authenticated SQL injection in EmailTrack that lets attackers write files and execute code as root.

cPanel disclosed CVE-2026-67401 on September 8, 2026: a SQL injection in the EmailTrack feature that allows authenticated account holders with mail-related permissions to create arbitrary files and execute code with root privileges. Fixes shipped in v11.110.0.143, v11.134.0.55, v11.136.0.39, v11.138.0.4, and WP2 channel v11.138.1.9, with all supported versions before those releases affected. Root-level execution poses severe risk to shared hosting providers and multi-tenant servers, as it removes isolation between cPanel accounts, websites, mailboxes, and backups. Researchers Ali Mustafa (rz1027) and abed1526 responsibly reported the flaw.

GBHackers · 7d agoVulnerabilityCVE-2026-67401

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

What’s the Scam?

Bruce Schneier reports AI-generated fake thank-you replies to his newsletter confirmations from throwaway Gmail accounts; the scam's goal is unclear.

Bruce Schneier describes receiving a burst of AI-generated, one-line praise emails replying to Crypto-Gram newsletter confirmation messages, sent from random-character Gmail addresses. None of the senders actually subscribed, and they did not respond when he replied, weakening a pig-butchering theory. The campaign appears automated, but its objective has not been identified.

Schneier on Security · 15d agoPhishing & fraud

New Chaos Variant Targets Misconfigured Cloud Deployments, Adds SOCKS Proxy

Darktrace says the Chaos botnet now targets misconfigured cloud deployments like Hadoop and added a SOCKS proxy for traffic relaying.

Darktrace identified a new 64-bit ELF variant of the Chaos botnet targeting misconfigured cloud deployments, expanding beyond the malware's traditional focus on routers and edge devices. Captured in a deliberately misconfigured Hadoop honeypot instance, the intrusion began with an HTTP request creating an application that ran embedded shell commands to fetch the Chaos agent binary from pan.tenire[.]com, set chmod 777 permissions, execute it, and delete the artifact to reduce forensic traces. The restructured variant adds a SOCKS proxy feature letting compromised systems ferry attacker traffic, while removing SSH-based spread and router-exploit functions, suggesting monetization beyond crypto mining and DDoS-for-hire. Possible Chinese origin is suggested by language artifacts and infrastructure; the delivery domain was previously used in Silver Fox's Operation Silk Lure phishing campaign delivering ValleyRAT.

The Hacker News · 29d agoMalware1

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

Iranian hackers use CHOSEN BRICK data-stealing malware to spy on dissidents and journalists

UK NCSC, FBI and Dutch AIVD warn Iranian state hackers deploy CHOSEN BRICK spyware via WhatsApp and Telegram lures against dissidents and journalists since 2025.

The UK's NCSC, the FBI and the Netherlands' AIVD jointly warned that Iranian state cyber actors have deployed CHOSEN BRICK against dissidents, activists and journalists in the UK, US and Netherlands since at least 2025. Victims are contacted on WhatsApp or Telegram by impostors posing as known contacts or platform support, then tricked into running files disguised as software such as fake Norton Antivirus, KeePass, Telegram or MRI scan results. The Windows malware adds Microsoft Defender exclusions, persists via HKCU Run keys, uses per-device Telegram bots for C2, and can capture screens, activate microphones, steal email and messaging data, and download further payloads. Some stolen data has later appeared on pro-Iranian leak sites, and the agencies note Iranian intelligence has plotted kidnappings or lethal operations against targets abroad.

Help Net Securityupdated · 2h agofirst · 13h agoThreat actor in the wild 6 sources

**Subject:** CVE-2026-2035703: Tozed ZLT X300 5G CPE — Unauthenticated Remote Root Code Execution via TR-069 Command Injection (CVSS 9.8)

Tozed ZLT X300 5G CPE firmware 6.01.3 has an unauthenticated TR-069 command injection (CVE-2026-2035703, CVSS 9.8) enabling root code execution.

Tozed ZLT X300 5G CPE router firmware 6.01.3 contains an OS command injection (CWE-78) in the TR-069/CWMP client daemon netcwmpd, tracked as CVE-2026-2035703 with CVSS 9.8. The IPPingDiagnostics Host parameter is passed unsanitized into sprintf, and the resulting shell command executes via system_by_root() as root. An attacker operating a rogue LTE base station built from roughly $300 of SDR hardware can impersonate the carrier's Auto Configuration Server and inject arbitrary commands. The disclosure does not report any observed exploitation.

Banking Trojans: Ursnif Global Distribution Networks Identified

Unit 42 maps banking-trojan distribution networks: spam botnets push Shiotob downloaders and Ursnif, KINS, Tinba at Japan and European targets via compromised web servers.

Unit 42 identified the distribution networks behind banking trojan attacks against Japan, Italy, Spain, Poland, Australia, and Germany. A spam botnet delivered 75 unique Shiotob (Bebloh/URLZone) variants across 7 million spam emails, with Shiotob acting mainly as a downloader that installs Ursnif and the Pushdo spam bot from C2 commands. Over 200 malicious files were hosted on 74 compromised, mostly European small-business web servers between April 2015 and January 2017, with localized invoice and photo-themed email lures per target country.

Palo Alto Unit 42 · Aug 17, 2026Malware in the wild

PoisonedRefresh: A Fileless Linux Rootkit That Injects PHP Web Shells Into F5 BIG-IP APM Server Memory

Sophos details PoisonedRefresh, a fileless Linux rootkit that injects a memory-resident PHP web shell into F5 BIG-IP APM after exploitation of CVE-2025-53521.

On September 8, 2026, SophosLabs published an analysis of Linux/Agnt-IC (dubbed PoisonedRefresh by ESET) found in compromised F5 BIG-IP Access Policy Manager environments. Initial access leverages CVE-2025-53521, an unauthenticated RCE in BIG-IP APM when an access policy is configured on a virtual server; F5 confirmed exploitation and links the activity to cluster c05d5254, while Shadowserver observed 795 exposed vulnerable endpoints. A first stage hidden in a modified umount binary modifies /usr/sbin/httpd and SELinux configuration and embeds itself in BIG-IP upgrade images for persistence. The second-stage ELF intercepts __libc_start_main, hooks apr_dso_load, and injects a PHP web shell into libphp memory via mmap manipulation, leaving no disk artifacts, and exposes a /bin/bash shell via a local UNIX domain socket instead of a TCP port.

Security Affairs · 7d agoMalware in the wildCVE-2025-53521