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Hackers Actively Exploit Critical WooCommerce Plugin Vulnerability to Upload PHP Backdoors

Attackers actively exploit CVE-2026-27540 (CVSS 9.8) in WooCommerce Wholesale Lead Capture plugin to upload PHP webshells; patch shipped in version 2.0.3.2.

CVE-2026-27540 (CVSS 9.8) in the WooCommerce Wholesale Lead Capture plugin affects versions 2.0.3.1 and earlier across roughly 6,000 active installations. The unauthenticated AJAX handler wwlc_file_upload_handler trusts a client-supplied file_settings allowlist, letting attackers upload shell.php for remote code execution. Wordfence has blocked more than 100,000 exploit attempts since disclosure, with spikes in June, July, and August 2026. The vendor fixed the flaw in version 2.0.3.2.

GBHackersupdated · 8h agofirst · 1d agoExploit / PoC in the wild 6 sourcesCVE-2026-27540

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

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

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

[webapps] webpack_devserver 5.2.5 - CSRF

Exploit-DB published a cross-site request forgery proof of concept for webpack_devserver 5.2.5.

Exploit-DB lists a webapps CSRF proof-of-concept against webpack_devserver version 5.2.5. The flaw affects the local webpack development server, where cross-site requests could be issued against it. No CVE id is cited in the entry and no active exploitation is reported.

Exploit-DB · Aug 17, 2026Exploit / PoC

ApateWeb: An Evasive Large-Scale Scareware and PUP Delivery Campaign

Unit 42 uncovers ApateWeb, a campaign using over 130,000 domains and multilayered redirects to deliver scareware, adware and PUPs to millions of users.

Unit 42 discovered ApateWeb, a large-scale campaign using a network of more than 130,000 domains to deliver scareware, potentially unwanted programs, adware including a rogue browser and browser extensions, and scam pages. The campaign uses a three-layer structure with deceptive emails as the entry point, centralized victim tracking via UUIDs, intermediate adware or anti-bot redirections, and evasion tactics such as cloaking, bot detection error pages, and wildcard DNS abuse. Activity spiked since August 2022, with several hundred attacker-controlled sites remaining in Tranco's top 1 million rankings and millions of monthly hits; Unit 42 blocked an estimated 3.5 million sessions across 74,711 devices in November 2023.

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

ClickFix moves into the browser: Cryptocurrency theft with Google-hosted C2

Talos tracks a crypto-theft campaign abusing the Google Visualization API for C2, using browser-based ClickFix lures to inject web-skimmer JavaScript.

Criminal actors convinced targets to paste JavaScript into Chrome's address bar or install it in the Tampermonkey extension, injecting a web skimmer into sessions on two cryptocurrency trading websites; Tampermonkey also provides persistence. Since March 2026 the campaign retrieved obfuscated scripts via the Google Visualization API from public Google Sheets documents, hooking the fetch API and replacing cryptocurrency deposit addresses in responses and the clipboard. Lures pose as leaked reports of a nonexistent API flaw at cryptocurrency swap services and spread via Telegram, DarkForums, and paste sites since early October 2025. Talos warns the legitimate-service-abuse techniques could enable wider supply-chain attacks on e-commerce and customer-facing systems.

Cisco Talos · 8d agoPhishing & fraud in the wild

Researcher shows how Claude Code can be tricked simply by asking it to summarize a website

Researcher wunderwuzzi showed Claude Code can be hijacked via prompt injection simply by asking it to summarize a website.

Security researcher Johann Rehberger (wunderwuzzi) demonstrated that Claude Code can be manipulated through prompt injection by simply asking it to summarize a website. Instructions embedded in fetched web content are executed by the agent, hijacking its behavior. The Register frames the finding as another demonstration of prompt injection risks in agentic coding tools that ingest untrusted web content.

The Register · Security · 19d 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 · 14d agoAI safety & security

ClickFix Moves into the Browser to Steal Cryptocurrency

Cisco Talos details a ClickFix campaign injecting browser JavaScript via Google Sheets to skim crypto deposits, stealing at least ~0.159 BTC since October 2025

Cisco Talos reported a months-long ClickFix campaign that shifted from OS command execution to injecting JavaScript through Chrome's address bar or the Tampermonkey extension into sessions on two cryptocurrency trading sites. Since March 2026 the operators fetch obfuscated payloads via the Google Visualization API from public Google Sheets, replacing displayed deposit addresses and amounts and overriding the fetch API, and the campaign survived two disruption attempts. Talos observed 49 Bitcoin addresses with 24 receiving at least 0.159 BTC (~$10,000) by early August, with proceeds routed through roughly 30 wallets and more than 3,000 addresses in apparent mixing. Lures posed as leaked vulnerability reports describing non-existent API flaws at crypto swap services, promising payouts up to 38% higher.

Infosecurity Magazine · 7d agoPhishing & fraud in the wild

You Get What You Sample: Evaluating Sampling Strategies for Web Security Measurements

Evaluation of 500k Tranco and 24.8M Common Crawl hosts shows Top-N domain sampling biases web security measurements; probability sampling yields unbiased estimates.

The study is the first comprehensive investigation of how sampling strategies affect web security measurement conclusions, comparing datasets and strategies across 500k Tranco domains and 24.8M Common Crawl hosts. It shows Top-N selection does not reflect the overall web distribution and may bias observed vulnerability rates, while probability-based strategies yield stable, unbiased prevalence and impact estimates. Hybrid sampling offers no advantage because its deterministic prefix consistently hurts accuracy, and the authors propose an adaptive probability-based strategy effective even when target prevalence is unknown.

arXiv cs.CR · 6d agoResearch1

Apple iCloud Private Relay Can Expose Real IPs Through WebKit Proxy Bypasses

Researchers found WebKit features bypass proxies and iCloud Private Relay, leaking users' real IP addresses; Apple patched in iOS 26.6.1 and macOS 26.6.2.

Researchers Talal Haj Bakry and Tommy Mysk found that three WebKit features — DNS prefetching, WebAuthn Related Origin Requests, and WebTransport — bypass configured proxies and send traffic directly from the device. This leaks the user's real IP address in Safari and all WebKit-based iOS browsers and undermines iCloud Private Relay's dual-hop privacy design. Any website can trigger the leak via WebAuthn without user interaction or passkey use; a proof-of-concept site, leaks.psylo.app, demonstrates the issue. Apple investigated and patched the leaks in iOS 26.6.1 and macOS 26.6.2.

The Hacker News · 17d agoVulnerability

Trends in Web Threats in CY Q2 2022: Malicious JavaScript Downloaders Are Evolving

Unit 42 detected 751,000 landing URL incidents in Q2 2022 and documented malicious JavaScript downloaders evolving to evade detection.

Unit 42 detected 751,331 landing URL incidents (253,644 unique) and 1,744,629 malicious host URL incidents (256,844 unique) from April through June 2022. Total landing URL incidents rose compared with Q1 2022, and unique host URL incidents grew 42%, indicating attackers deploying more variants. The report includes a case study of a JavaScript downloader campaign demonstrating new evasion techniques. Personal sites, blogs, and business sites were the top apparently benign entry points.

Palo Alto Unit 42 · Aug 17, 2026Research

Attackers Actively Exploiting Critical Vulnerability in WooCommerce Wholesale Lead Capture Plugin

Attackers are actively exploiting an unauthenticated arbitrary file upload flaw in the WooCommerce Wholesale Lead Capture plugin, enabling PHP backdoors and remote code execution.

A critical unauthenticated arbitrary file upload vulnerability in WooCommerce Wholesale Lead Capture, a premium WordPress plugin with an estimated 6,000 active installations, was publicly disclosed on February 20, 2026. Wordfence reports attackers are now actively exploiting the flaw to upload arbitrary files, including PHP backdoors, and achieve remote code execution. No CVE ID was cited in the report.

Wordfence · 2d agoExploit / PoC in the wild1

Trends in Web Threats: Old Web Skimmer Still Active Today

Unit 42 detected 577,000 landing URL incidents in Q1 2022, with an old web skimmer family still actively stealing payment card data.

Palo Alto Unit 42 detected 577,275 landing URL incidents (116,643 unique) and 2,043,862 malicious host URL incidents (180,370 unique) between January and March 2022. Web threat volumes declined after the November 2021 holiday peak, but an old web skimmer family remained active. Business and economy sites overtook personal sites as the most common apparently benign entry points. Most malicious domains geolocated to the United States, Germany, and Russia, though proxy servers and VPNs obscure true locations.

Palo Alto Unit 42 · Aug 17, 2026Research

[webapps] CubeCart 6.7.4 - Stored XSS

A proof-of-concept stored cross-site scripting exploit targeting CubeCart 6.7.4 was published on Exploit-DB.

Exploit-DB lists a proof-of-concept exploit for a stored cross-site scripting (XSS) vulnerability in CubeCart 6.7.4, a PHP-based e-commerce web application. The listing demonstrates injection of attacker-controlled script that persists in the application, but no exploitation in the wild or CVE assignment is reported in the provided text.

Exploit-DB · 16d agoExploit / PoC1

VU#614868: OpenCart ecommerce platform contains directory traversal vulnerability

OpenCart 4.2.0.0 extension installer fails to validate zip extraction paths, allowing directory traversal (CVE-2026-18412) to write files outside intended directories.

CERT/CC VU#614868 discloses CVE-2026-18412, a directory traversal vulnerability in OpenCart v4.2.0.0's extension installer. The installer extracts uploaded .ocmod.zip files using zip entry filenames as filesystem paths without verifying the resolved path stays inside the intended directory. A malicious extension zip could result in arbitrary file writes outside the target directory.

CERT/CC Vulnerability Notes · Aug 10, 2026VulnerabilityCVE-2026-184121

VU#308749: Remote Code Execution and Arbitrary File Read Vulnerabilities in Kaltura Servers

Insecure deserialization in Kaltura's legacy HTML5 Player V2 (mwEmbed) allows arbitrary file read and remote code execution; Player V7 is unaffected.

CERT/CC issued VU#308749 for two flaws in Kaltura's HTML5 Player V2 library (mwEmbed/html5lib), both caused by the same insecure deserialization bug. The flaws enable arbitrary file read and remote code execution via the exposed mwEmbedLoader.php endpoint. Affected versions include html5lib v2.45, v2.103 and earlier, and other v2.x releases; the currently supported Player V7 is unaffected. No evidence of exploitation was cited.

CERT/CC Vulnerability Notes · 22d agoVulnerability

Brevo supply chain attack hits 100k+ sites with Wordpress backdoors and Clickfix malware

Attackers with Brevo DNS access injected malicious scripts serving ClickFix malware and WordPress backdoors to over 100,000 customer sites on 14 September 2026.

Brevo (formerly Sendinblue), an email marketing platform whose clients include eBay, Louis Vuitton, Michelin and Amnesty International, served injected JavaScript from sendibt1.com domains between 16:05 and 20:12 UTC on 14 September 2026, reaching over 100,000 customer sites and mailing lists. The f.js malware secretly installed a WordPress backdoor plugin from cdn10.sendibt1.com/p/wm.zip using logged-in admins' sessions and showed ClickFix overlays urging visitors to copy-paste and run commands. An SSL certificate for cdn.sendibt1.com created August 25 and attacker-created cdn* DNS records indicate write access to Brevo's Cloudflare DNS, likely via a single Cloudflare account compromise. Sansec recorded 2,549 CSP violation reports across 12 monitored sites; all malicious hosts stopped resolving on 15 September and Brevo's status page lists no incident.

Sansec (Magento / e-commerce security) · 23h agoMalware in the wild

JSCeal Malware Can Bypass Google Authentication Using Stolen Session Cookies

Check Point details JSCeal, a V8-compiled JavaScript stealer that replays stolen cookies to bypass Google authentication, spread via crypto malvertising.

Check Point Research's new report analyzes JSCeal, a compiled V8 JavaScript malware obfuscated with javascript-obfuscator using RC4-protected strings, control-flow flattening, and proxy functions. Delivered through fake TradingView installers on malvertising sites overlapping the WEEVILPROXY/MeadowLocust and SourTrade campaigns, it harvests cookies, passwords and OAuth tokens from Chromium browsers, records keystrokes and screenshots, and can replay stolen Google session cookies to bypass authentication. It also installs a local proxy with service-specific handlers for Binance, Bybit, and Ledger to intercept and modify cryptocurrency-related traffic.

The Hacker News · 9d agoMalware in the wild1

terms.txt: A Consent and Compensation Protocol for Agentic Web Access

terms.txt specifies a robots.txt-style protocol for per-path, per-purpose AI crawler consent and compensation, with enforcement adding 0.20-0.65 ms per request.

The paper documents that automated clients now make up most web requests, that training dominates Cloudflare-classified crawling, and that the largest AI platforms fetch thousands of pages per returned visitor while robots.txt cannot express identity, purpose, terms, or price. It specifies terms.txt plus an origin-enforced exchange using Web Bot Auth signatures, signed intent, delegation tokens, HTTP 402 negotiation, and signed receipts. A dependency-free implementation adds 0.20 to 0.65 ms per request on one vCPU.

arXiv cs.CR · 6d agoResearch

Infostealers are hijacking Claude accounts at users’ expense

Malwarebytes reports infostealers are stealing Claude session cookies to hijack Anthropic accounts and consume victims' usage at their expense.

Anthropic warned that infostealer malware operators are harvesting Claude session cookies from infected machines. Attackers replay the stolen cookies to take over users' accounts and consume their usage quotas, affecting the victims' own access. The activity involves observed account hijacking rather than a flaw in Claude itself.

Malwarebytes Labs · 15d agoMalware in the wild

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

WordPress Plugins Compromised Without a Single File Change

Attackers poisoned bdThemes' JSON API feed to backdoor WordPress sites by serving malicious remote code without modifying plugin files.

Infosecurity Magazine reports a supply chain attack in which attackers poisoned a JSON feed used by bdThemes WordPress plugins. The compromised feed delivered malicious code that backdoored sites without changing any plugin files, evading file-integrity based detection. WordPress sites running the vendor's plugins were affected.

Infosecurity Magazine · Aug 10, 2026Malware in the wild

Malicious Apache Modules Hijack Brazilian Government Site Traffic to Push Betting Pages

Check Point links Gambling Goblin, a Chinese-speaking cluster, to malicious Apache modules hijacking Brazilian government servers to promote betting sites.

Check Point Research tracks Gambling Goblin, a Chinese-speaking cluster, installing malicious Apache reverse-proxy modules on compromised Brazilian government and education web servers since mid-2025. The modules divert visitors to gambling and fake app-store pages while stripping the site's security headers, likely for large-scale SEO manipulation. The group's Linux arsenal includes DownPro, AlphaAgent, oRAT, a 3snake-based credential stealer, and SSH brute-forcing tools, and it is tied to Trend Micro's Earth Berberoka. Related SEO-fraud campaigns on .gov.br domains were documented by ESET (GhostRedirector), Palo Alto Networks Unit 42, and Hunt.io.

The Hacker News · 14d agoThreat actor in the wild

New Phishing Attacks Use Trusted Email Infrastructure and URL Cloaking to Bypass Security Tools

Virus Bulletin Q3 2026 report details phishing using DKIM-aligned senders, Amazon SES delivery, and real-time URL cloaking to evade email security and scanners.

Virus Bulletin's Q3 2026 testing found phishing campaigns delivered through trusted infrastructure like Amazon SES with DKIM-aligned sender domains. Samples included a German overdue-invoice lure redirecting to OpenSea crypto fraud and a Romanian BCR-branded PSD2 banking credential-theft campaign. Cloaking pages used hidden iframes, browser fingerprinting, and time-zone checks to show different content to scanners versus victims. Defenders are urged to inspect full redirect chains rather than attachments or initial URLs alone.

Cyber Security Newsupdated · 1d agofirst · 1d agoPhishing & fraud in the wild 2 sources