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SloppyRAT: A New Tool For Ransomware Attacks

Zscaler details SloppyRAT, a new DLL backdoor delivered via ClickFix lures that stages CastleLoader and CastleRAT ahead of ransomware attacks.

Zscaler ThreatLabz analyzed SloppyRAT, a DLL-based backdoor distributed via ClickFix lures that abuses finger.exe over TCP port 79 to download a batch script. The malware copies curl.exe to download IronPython 3.4.2 from GitHub and executes zlib-compressed Base64-encoded Python to deploy CastleLoader and CastleRAT, then reflectively loads SloppyRAT in memory. It hinders analysis using XOR stack-string obfuscation, a modified affine cipher with modulus 127, and 13 runtime-decrypted code blocks, while communicating with C2 over a reverse SOCKS channel.

Zscaler ThreatLabzupdated · 5d agofirst · 6d agoMalware in the wild 3 sources

Search results are sending people to fake Bitrefill checkouts

Scam sites impersonating Bitrefill's crypto checkout appear in search results, tricking victims into sending up to $1,990 in crypto directly to scammers.

Malwarebytes documents a cluster of lookalike domains copying Bitrefill's gift card checkout, surfaced via search engine results rather than email. Victims choose an amount up to $1,990 and pay in Bitcoin, Ethereum, USDC, USDT, Solana, or Litecoin to scammer-controlled addresses, with no recourse since crypto payments are irreversible. Domains use typosquatting and Punycode/IDN homoglyph tricks, and the fake sites run commercial analytics software to measure and optimize victim conversion. Bitrefill's security team is working with takedown specialists to remove the sites.

Malwarebytes Labs · 1d agoPhishing & fraud

TerminalFix campaign deploys a reverse tunnel through multistage intrusion

Microsoft Threat Intelligence details the TerminalFix campaign, which uses fake CAPTCHA prompts, DLL sideloading, and reverse tunnels in multistage intrusions.

Microsoft Threat Intelligence published analysis of a ClickFix-style campaign dubbed TerminalFix. The intrusion chain relies on fake CAPTCHA social engineering and DLL sideloading, and the attackers deploy a reverse tunnel to maintain access through a multistage intrusion. Microsoft released detections and threat hunting guidance for defenders.

Microsoft Security Blog · 18d agoThreat actor in the wild

Trusting-Trust Attack against an Entire Linux Distribution (via the strip utility)

ArXiv paper shows the trusting-trust compiler backdoor technique can compromise an entire Linux distribution via the strip utility.

The paper (arXiv 2607.24888) demonstrates that Ken Thompson's trusting-trust attack, long viewed as a compiler-specific threat, can backdoor an entire Linux distribution by targeting the strip utility. A compromised tool reproduces its backdoor in subsequent rebuilds of itself, generalizing the attack surface beyond compilers. The finding has supply-chain implications for build reproducibility and distribution trust, though it is a research result with no observed real-world exploitation.

Lobsters · security · 11d agoResearch

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

Version Control DFIR: a Cheatsheet to GitHub, GitLab, Bitbucket, and Azure DevOps

Wiz published a DFIR cheatsheet covering log visibility, incident readiness, and threat hunting across GitHub, GitLab, Bitbucket, and Azure DevOps.

Wiz researchers released a practitioner's guide to version control system forensics, incident response, and threat hunting. The cheatsheet maps log sources, audit capabilities, and hunting workflows across GitHub, GitLab, Bitbucket, and Azure DevOps. It aims to improve incident readiness for source code and CI/CD compromise scenarios.

Wiz Blog · 20d agoResearch1

Hackers Abuse Google Sheets to Hijack Crypto Wallet Addresses in ClickFix Attacks

Cisco Talos details a crypto-theft ClickFix campaign abusing Google Sheets to swap wallet addresses, with about $10,000 in observed Bitcoin losses.

Cisco Talos tracks a ClickFix-style campaign that tricks cryptocurrency traders into pasting JavaScript into Chrome's address bar or a Tampermonkey extension, promising fake bonuses on SwapZone and SimpleSwap. The loader pulls obfuscated JavaScript from cells in a public Google Sheet via the Visualization API, then behaves like a web skimmer, rewriting deposit addresses on screen, in web responses, and in the clipboard. Researchers counted 49 attacker-controlled Bitcoin addresses, with 24 receiving a combined 0.159 BTC, roughly $10,000, by early August 2026. A Tampermonkey variant re-injects the payload on every return visit, giving the attackers persistence despite takedown efforts.

Cyber Security News · 7d agoPhishing & fraud in the wild

C2Looper: A New Backdoor Likely Tied To Ransomware With GitHub C2

Zscaler ThreatLabz identified C2Looper, a new Rust-based backdoor likely tied to ransomware actors and delivered via ClickFix chains, using GitHub for C2.

In July 2026, Zscaler ThreatLabz identified C2Looper, a new Rust-based backdoor family. The malware supports arbitrary command execution, reconnaissance, and deployment of second-stage payloads, and uses GitHub as its command-and-control channel. ThreatLabz assesses with low-to-medium confidence that it is delivered through multi-stage ClickFix infection chains and is likely leveraged by a ransomware-related threat actor. The analysis covers multiple C2Looper variants, their network protocols, and capabilities.

Zscaler ThreatLabz · Aug 17, 2026Malware in the wild1

A Princeton Researcher Proposes Recurrent Looped Transformer (RLT) that Carries Decoder State across Every Token, Fixing 96 Blocks per Token with Unbounded Temporal Depth

Princeton researcher Yifan Zhang proposes Recurrent Looped Transformer, carrying full decoder state across every token for unbounded temporal depth.

Yifan Zhang's technical report defines the Recurrent Looped Transformer (RLT), pairing a causal encoder with a recurrent decoder whose final output and layerwise sliding-window attention cache carry into every subsequent token with no prompt-response boundary reset. The reference configuration ties 48 encoder and 48 decoder layers, executing 96 logical blocks per token while the state path grows to 48t blocks after t tokens at fixed per-token compute. The report details RL replay contracts that rebuild all states under current parameters and exact prefix snapshots for multi-turn serving, but explicitly reports no measured efficiency, reasoning quality, or scaling results.

MarkTechPost · 3d agoAI research1

BTR Reforged: Weaponizing Defender’s Remediation Driver as a Kernel Operation Primitive

Check Point shows attackers can abuse Microsoft Defender's signed remediation driver for arbitrary Ring 0 file and registry operations without exploiting any vulnerability.

Check Point Research presents BTR Reforged, a technique that repurposes Microsoft Defender's trusted remediation driver into an attacker-controlled kernel operation primitive. The signed driver can be instructed to execute arbitrary file and registry operations from Ring 0 without exploits, vulnerabilities, or memory corruption. The work demonstrates how trusted security components can be turned into attacker primitives, which is relevant for defenders assessing driver abuse risks.

Check Point Research · 27d agoResearch

Liquid Hackers Return 3,400 Bitcoin Taken via Elements Bug, Still Holding $47M in BTC

Hackers exploited an Elements bug to take ~4,000 BTC from Liquid Network, returned 3,400 BTC (~$265M), and still hold ~598.5 BTC (~$47M).

Attackers exploited a bug in Elements, the software behind Blockstream's Liquid Network Bitcoin sidechain, to create L-BTC and withdraw roughly 4,000 BTC (about $320 million) via SideSwap's Peg-out Authorization Key, roughly 95% of Liquid's reported reserves. They returned 3,400 BTC (about $265 million at ~$78,000 per BTC) to the federation address on September 7, keeping about 598.5 BTC (roughly $47 million). The group called itself white hats, demanded node patches before returning funds, and negotiated via on-chain and PGP-encrypted messages; Ledger CTO Charles Guillemet characterized the arrangement as extortion. Blockstream says the peg-out key and other keys were not compromised, updated software is deployed, and the network remains paused pending a coordinated restart.

The Hacker News · 8d agoExploit / PoC in the wild

Hackers deploy Linux rootkit on F5 BIG-IP APM devices, hiding web shell in memory

Sophos analyzed a Linux rootkit, tracked as PoisonedRefresh, on hacked F5 BIG-IP APM devices hiding an in-memory web shell linked to exploited CVE-2025-53521.

Sophos and ESET analyzed an implant (named PoisonedRefresh by ESET) deployed on compromised F5 BIG-IP APM appliances, which serves enterprise, financial, government, and public sector deployments. The second-stage payload intercepts __libc_start_main, hooks Apache's APR module loader (apr_dso_load), RC4-encodes key strings, and rewrites PHP file reads in memory to embed a web shell inside legitimate scripts like apm_css.php3, full_wt.php3, and webtop_popup_css.php3, leaving on-disk files unchanged. A related installer component infects /usr/sbin/httpd, persists across BIG-IP upgrade images, modifies SELinux configuration, and deploys the payload. The malware also creates a Unix domain socket at /run/bigtlog.pipe that hands authenticated local connections to /bin/bash; F5 links the activity to CVE-2025-53521, an unauthenticated RCE in BIG-IP APM already exploited in the wild.

Help Net Security · 7d agoMalware in the wildCVE-2025-535211

Attack hides malware in PNGs and drops custom reverse tunnel on victims' machines

A ClickFix social engineering wave delivers a multi-stage attack that hides malware in PNG files and installs a custom reverse tunnel.

The Register reports a new wave of ClickFix social engineering attacks that trigger a multi-stage infection chain on victim machines. The attack reportedly conceals malware inside PNG image files and deploys a custom reverse tunnel tool for attacker access. Further technical details are limited in the available text.

The Register · Security · 16d agoMalware in the wild

Hackers Abuse Google Sheets as C2 in ClickFix Attacks to Steal Cryptocurrency

Cisco Talos tracks a ClickFix crypto-theft campaign using Google Sheets as C2 to swap deposit addresses in Chrome.

Cisco Talos uncovered a cryptocurrency theft campaign that abuses Google Sheets and the Google Visualization API as a covert C2 channel, delivering obfuscated JavaScript into victims' Chrome browser sessions via ClickFix-style social engineering. Victims are lured with a fake "API Logic Flaw" report promising 25-38% bonuses on SimpleSwap and SwapZone swaps; the injected payload acts as a browser-based web skimmer that replaces deposit addresses, overrides the fetch API, and hijacks the clipboard. Later variants use the legitimate Tampermonkey extension with a user script for persistence without OS-level compromise. Talos identified 49 Bitcoin wallets, with 24 reused addresses receiving about 0.159 BTC (~$10,000) before mixing through more than 3,000 addresses.

GBHackers · 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

Hackers demand 10,000 Bitcoin from Revolut following data breach

Revolut breach via spoofed government-agency email requests; attackers posted stolen data samples on Telegram and demand 10,000 Bitcoin.

Revolut disclosed that an unauthorized third party obtained sensitive customer information by sending fraudulent requests from the email domain of a legitimate government agency. People claiming responsibility have posted samples of the allegedly stolen data across several Telegram groups. The perpetrators are demanding 10,000 Bitcoin from Revolut.

DataBreaches.net · 1d agoData breach

Rust Supply Chain Attack on arrayref: Significant Overlap with DPRK Campaigns

Malicious versions of the Rust crate arrayref executed a compile-time backdoor, with infrastructure overlapping recent DPRK supply chain attacks on Mastra and axios.

Wiz researchers report that malicious versions of the arrayref Rust crate ran a backdoor during compilation, compromising developer build pipelines. The campaign's command-and-control infrastructure significantly overlaps with infrastructure used in recent DPRK supply chain attacks, including campaigns against Mastra and axios. Developers using affected crate versions should audit their builds and review dependencies.

Wiz Blog · 27d agoThreat actor in the wild1

JSCeal Hides Crypto Malware in V8 Bytecode

Check Point details JSCeal, a crypto-stealing malware delivered as compiled V8 bytecode, and built a decompiler pipeline to expose its capabilities.

JSCeal, tracked by Check Point Research since early 2025, is a cryptocurrency stealer delivered as heavily obfuscated JavaScript compiled to V8 bytecode (.jsc) and run by a bundled Node.js runtime. Check Point, presenting at Black Hat USA 2026, extended the open-source View8 decompiler into a pipeline that recovered readable code from 23 samples, revealing theft of browser credentials and cookies, Telegram sessions, keystrokes, screenshots, HTTPS traffic interception with attacker-controlled certificates, and automated Google account takeover. Targeted overrides rewrite content for Binance, Bybit, and Ledger users. Later samples added AES-256-CBC encryption with externally supplied keys and expanded targeting to macOS.

Security Affairs · 9d agoMalware1

You've Got a BUD in Me: Authenticated Reads from Per-Block Write Logs

Researchers propose BUD, per-block write-log digests enabling blockchain validators to serve historical membership and exclusion proofs far cheaper than state-wide tries.

The paper introduces Block Update Digests (BUD), which authenticate each block's write log with predecessor pointers, plus a SuperBUD and exponential hierarchy to turn long unchanged intervals into short proofs. Soundness against adversarial provers and up to f Byzantine validators is proven under archive, attestation, and committee evidence assumptions. Benchmarks show a 50x state-size increase raises the base-BUD path only 1.24x versus 3.1x for in-memory and 69.5x for disk-backed Merkle Patricia tries, with read payloads below 800 bytes and p99 warm verification at 146 microseconds.

arXiv cs.CR · 6d agoResearch

Operational Roles of QRNG-Derived Quantum Entropy in Bitcoin Proof-of-Work Architectures

arXiv study finds quantum-random entropy adds no Bitcoin PoW success advantage but helps assurance in fault and provenance scenarios.

The paper shows replacing classical entropy with QRNG output does not change honest Bitcoin proof-of-work success probability when candidate headers remain distinct. It introduces a reproducible benchmark measuring an entropy-efficiency factor and a reboot-diversity index, finding QRNG value only in assurance-oriented scenarios involving correlated restart faults, namespace reuse, and entropy provenance. Validation is simulation-based, with hardware-in-the-loop testing identified as future work.

arXiv cs.CR · 12d agoResearch

A hacker stole $340M in a crypto heist, then returned most of it

A hacker exploited a bug to steal about 4,000 BTC (~$340M) from Blockstream's Liquid Network, then returned roughly 3,400 BTC after the bug was fixed.

A hacker exploited a bug to withdraw roughly 4,000 bitcoins worth about $340 million from Liquid Network, a settlement service launched in 2018 by crypto firm Blockstream and used by several cryptocurrency exchanges. Liquid Network paused operations, and the hacker, described as a white hat, offered to return the funds once the bug was fixed. Former Blockstream executive Samson Mow said the bug was fixed and about 3,400 BTC (~$293M) returned, leaving roughly 600 BTC (~$47M) under the hacker's control pending further security improvements. Rekt's leaderboard ranks the heist among the largest cryptocurrency thefts to date.

TechCrunch · Security · 8d agoExploit / PoC in the wild

New Ted Backdoor Hides Inside Victims' Own HAProxy Builds to Intercept Web Traffic

Rapid7 found a new backdoor, ted, compiled into trojanized HAProxy at two South Korean organizations, with medium-confidence attribution to North Korean actors.

Rapid7 documented a previously undocumented Linux toolkit named ted compiled into the HAProxy load balancer binaries of two South Korean organizations in the automotive and media sectors. The implant intercepts web traffic, serves altered pages only to filtered visitors, and hides C2 exchanges from backend logs and HAProxy statistics; a companion RAT, curlRAT, beacons on a default 12-hour schedule. The toolkit also trojanizes crond, sshd, agetty, atd, and polkitd binaries and sanitizes logs and bash history. Rapid7 attributes the activity with medium confidence to North Korean state-sponsored actors, with domain infrastructure overlapping APT37 listings in maltrail and delivery resembling the Operation SyncHole campaign.

The Hacker News · 12d agoThreat actor 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

Hackers Drain $320 Million From Liquid Network, Then Return Most of It

Hackers exploited an Elements bug to drain about 4,000 BTC (~$320M) from Liquid Network's federation wallet, then returned 3,400 BTC after Blockstream patched.

An attacker drained roughly 4,000 of 4,200 BTC (~$320M) from Bitcoin's Liquid Network federation wallet on September 6 by exploiting a bug in Elements, the open-source code powering the sidechain, which allowed unbacked L-BTC tokens that were redeemed for real Bitcoin through SideSwap's authorized peg-out mechanism. The self-described white-hat attackers negotiated publicly via OP_RETURN on-chain messages, demanding the bridge nodes be patched before returning 3,400 BTC (~$262.6M) and keeping about 598 BTC (~$47M). Blockstream confirmed the affected bridge nodes were patched; the network remains paused while federation members complete security work, and experts debate whether the act legally constitutes extortion.

Security Affairs · 7d agoExploit / PoC in the wild

Vulnerabilities fixed in libxml2-2.15.4

libxml2 2.15.4 fixes an out-of-bounds read in xmlregexp's NXT macro plus several integer overflow and parsing flaws.

libxml2 2.15.4 (released September 1, 2026) includes security fixes: an out-of-bounds read in the xmlregexp NXT macro, missing overflow checks in dict.c, uri.c, and valid.c, an integer overflow in xmlIO before the writecallback, and an overflow check in xmlXPtrEvalXPtrPart. The release also propagates parseFlags in xmlXIncludeProcess and xmlXIncludeProcessTree. No CVE identifiers, exploitation, or severity ratings are given in the announcement.

oss-security · 11d agoVulnerability

Windows BitLocker Flaw Lets Attackers Execute Code on Vulnerable Systems

Microsoft patched CVE-2026-69449, a heap-based buffer overflow in Windows BitLocker allowing privileged local attackers to execute code; no exploitation reported.

Microsoft disclosed CVE-2026-69449 on September 8, 2026, an Important-severity heap-based buffer overflow (CWE-122) in Windows BitLocker with a CVSS 3.1 base score of 6.7. The attack vector is local (AV:L) with high privileges required, so exploitation needs privileged local access rather than remote access over the internet. Microsoft, as assigned CNA, has not reported public exploitation, and administrators are urged to inventory BitLocker-enabled systems and apply updates. Interim mitigations include least-privilege access, limiting administrative rights, and monitoring for unexpected elevated process activity.

GBHackers · 7d agoVulnerabilityCVE-2026-694491

Hackers drain $320M in Bitcoin from Liquid Network, claim they’re the good guys

Hackers withdrew roughly 4,000 BTC (about $320M) from the Liquid Network federation wallet backing the Blockstream-developed Bitcoin sidechain, claiming benign intent.

Blockstream said Sunday that around 4,000 BTC, roughly $320 million, was withdrawn from the federation wallet backing Liquid Network, a Bitcoin sidechain used by exchanges and financial institutions. The attackers publicly claimed they were 'the good guys'; no attribution or recovery details are provided. The theft affects infrastructure that backs custodial Bitcoin transfers for exchanges.

DataBreaches.net · 9d agoData breach in the wild