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Hackers Pose as Domain Controllers to Steal Active Directory Password Hashes

Attackers abuse Active Directory replication (DCSync) via the DRSUAPI protocol to steal password hashes and forge Golden Tickets for persistent domain compromise.

Security reporting citing Trellix details how threat actors impersonate domain controllers to request replication data and obtain NTLM password hashes without dumping LSASS on the domain controller. With Domain Admin or replication rights, attackers can steal the KRBTGT hash and forge long-lived Golden Tickets that survive password resets. Defenders should monitor DRSUAPI requests from non-DC systems, restrict replication permissions, and enforce MFA and tiered administrative access.

Cyber Security Newsupdated · 6d agofirst · 6d agoResearch 2 sources3· 1 read

Your DNS Is Hiding in HTTPS — This Is Why It Matters

Akamai argues that unmanaged DNS over HTTPS (DoH) creates enterprise visibility gaps and advocates controlled DoH strategies to restore DNS monitoring.

Akamai published a blog post arguing that unmanaged DNS over HTTPS encrypts DNS queries outside enterprise visibility, creating security monitoring gaps. The post advocates a controlled DoH strategy that restores DNS visibility for defenders while preserving user privacy. No specific incidents, vulnerabilities, or products are cited in the advisory-style piece.

Akamai Blog · 14d agoIndustry

Automatically Detecting DNS Hijacking in Passive DNS

Unit 42's machine learning pipeline detected 6,729 DNS hijacking events between March and September 2024, hitting political parties, ISPs, and universities.

Unit 42 processes roughly 167 million new DNS records daily and applies a machine learning model using 74 features over 169 TB of passive DNS and geolocation data to flag hijacked domains. From March to September 2024 the pipeline screened over 29 billion records and classified 6,729 as DNS hijacking, averaging 38 detections per day; a new model detects hijacks in customer traffic within about 10 minutes. Notable cases include a Hungarian political party's hijacked domain, defacement of a large utility company and ISP, and university and research center domains repurposed for illicit gambling. DNS hijacking typically relies on stolen registrar or DNS provider credentials or cache poisoning, enabling MitM attacks, phishing, drive-by downloads, and scams.

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

[remote] D-Link DNS_340L - OS Command Injection

An OS command injection exploit was published for the D-Link DNS-340L NAS, a flaw relevant to exposed network storage devices.

Exploit-DB published exploit #52643 for the D-Link DNS-340L network-attached storage device. The vulnerability is an OS command injection, which could allow arbitrary command execution on affected devices. The disclosure text does not report exploitation in the wild.

Exploit-DB · Aug 17, 2026Exploit / PoC

Advanced Dns Security

Palo Alto Networks Unit 42 hosts a product archive page for its Advanced DNS Security DNS-layer threat prevention service.

The page is a product category archive on the Unit 42 blog with no article text available. Advanced DNS Security is Palo Alto Networks' DNS-layer threat prevention offering. No research findings, incidents, or vulnerabilities are described.

Palo Alto Unit 42 · 8d agoIndustry 6 sources

Almost Half of Malware Samples Communicate Direct to IP

Unit 42 analysis of 4 million malware reports finds 45% of C2-active samples connect directly to hard-coded IPs, bypassing DNS defenses.

Palo Alto Unit 42 analyzed over 4 million Advanced WildFire dynamic analysis reports and found that 45.32% of malware samples with C2 activity made at least one direct-to-IP connection, accounting for 23.17% of all C2 connection attempts. The firm proposes zero trust IP (ZT-IP), an enforcement approach that verifies whether outbound destinations were ever sanctioned by a DNS response. ZT-IP analysis surfaced Phorpiex ransomware droppers fetching payloads directly from C2 IPs, a persistent data exfiltration campaign using an obfuscated \GET protocol, and Mozi P2P botnet payloads delivered to IoT devices without DNS. Only 1% of benign samples connected directly to untrusted IP addresses.

Palo Alto Unit 42 · Aug 17, 2026Research

Six new dnsmasq vulnerabilities open the door to DNS cache poisoning, local root

Six dnsmasq flaws enable DNS cache poisoning, DoS, memory leaks, and local root code execution; fixes ship in version 2.92rel2.

Researchers disclosed six dnsmasq vulnerabilities spanning memory safety and input validation, including heap buffer overflows in extract_name() and extract_addresses(), DNSSEC infinite-loop and out-of-bounds read flaws, and a DHCPv6 out-of-bounds write allowing local root code execution. Exploitation paths include DNS cache poisoning, bypassing security controls, remote denial of service, and local privilege escalation. Maintainers released version 2.92rel2 with fixes, and a stable 2.93 release is expected within weeks.

Autoencoder Is All You Need: Profiling and Detecting Malicious DNS Traffic

Palo Alto Unit 42 details an autoencoder-based method that profiles DNS traffic to detect C2 and malicious domains, blocking ~374,000 malicious DNS requests daily.

Unit 42 built an RNN-based autoencoder that compresses DNS traffic time series into fixed-dimensional 'DNS profiles' for each domain and device. Downstream classification, clustering, and anomaly detection modules flag suspicious domains, capturing 170 emerging suspicious domains in May 2024. Signatures block roughly 374,000 malicious DNS requests daily and run in the Advanced DNS Security service, with detections shared to Advanced URL Filtering. Case studies link DNS traffic patterns to C2 beaconing, dynamic DNS abuse, and DNS tunneling for data exfiltration.

Palo Alto Unit 42 · Aug 17, 2026Research

Next.js 16.4.0-canary.13 Image Optimizer DNS Rebinding TOCTOU SSRF Still Exists

Next.js 16.4.0-canary.13 Image Optimizer retains a DNS rebinding TOCTOU SSRF in fetchExternalImage() allowing requests to private network resources.

Next.js 16.4.0-canary.13 contains a DNS rebinding time-of-check-to-time-of-use Server-Side Request Forgery vulnerability in the Image Optimizer's fetchExternalImage() function. The code resolves the supplied hostname and checks the resulting addresses with isPrivateIp(), but a TOCTOU gap between resolution and the actual fetch allows an attacker-controlled DNS record to change and reach private network resources.

Full Disclosure · 12d agoVulnerability

Hacking Public Wi-Fi DNS to Steal Credentials

Attackers can hijack public Wi-Fi DNS to redirect users to credential-stealing fake login pages; commenters debate HTTPS limits and mitigations like encrypted DNS.

The discussion examines how an attacker controlling DNS on shared or public Wi-Fi networks can redirect requests for legitimate services to attacker-controlled servers to steal credentials. Commenters analyze whether HTTPS and certificates mitigate the attack, noting attackers often rely on HTTP or browser trust quirks. Suggested defenses include encrypted DNS (DoH), DNSSEC, and travel routers running OpenWRT. No specific campaign, victims, or indicators are provided.

Schneier on Security · Aug 17, 2026Research1

1.1.1.1 now supports post-quantum DNSSEC, all 2,420 bytes of it

Cloudflare's 1.1.1.1 resolver now validates post-quantum DNSSEC signatures using ML-DSA-44, a 2,420-byte NIST algorithm, preparing DNS for post-quantum migration by 2029.

Cloudflare enabled 1.1.1.1 to validate DNSSEC signatures using ML-DSA-44 (algorithm 18), a NIST-standardized post-quantum signature with 1,312-byte public keys and 2,420-byte signatures, roughly 38x larger than ECDSA P-256. The large signatures exceed common DNS-over-UDP limits, forcing fallback to TCP and creating downgrade risks while conventional algorithms must be published alongside. Cloudflare cites the risk of a quantum computer breaking RSA/ECDSA signatures by 2030 and plans full post-quantum security by 2029.

Cloudflare Blog · 6d agoTools1

[dos] LuCI DHCPv6 - Lease Hostname Stored Cross-Site Scripting

Stored cross-site scripting in OpenWrt LuCI via malicious DHCPv6 lease hostnames allows router interface attacks.

Exploit-DB entry 52637 describes a stored cross-site scripting vulnerability in LuCI, the OpenWrt web administration interface. A attacker on the local network can set a malicious hostname that gets stored in DHCPv6 lease data and rendered unsafely in the LuCI UI. When an administrator views the lease status page, the injected script executes in the router's management context.

Exploit-DB · Aug 11, 2026Exploit / PoC

Cavern C2 Uses DNS and Google Apps Script to Blend Into Legitimate Traffic

Kaspersky details Iranian Cavern Manticore's expanded C2 framework using DNS and Google Apps Script, plus APT42's TAMECAT spyware in nuclear-sector phishing.

Kaspersky reported new components in the Cavern (Cav3rn) C2 framework, used by Iranian MOIS-affiliated Cavern Manticore (with overlaps to MuddyWater and OilRig's Lyceum) against Israeli entities, monitored since December 2025. The new GoogleService.dll module performs DNS A-record queries to choose between direct HTTPS and a Google Apps Script relay per transaction, with the DNS infrastructure able to rotate the Google deployment ID; Kaspersky also found an inter-component broker (rnp.dll) and linked the framework's plugin-based pivot to late April 2026. Separately, Group-IB and Kaspersky detailed HOLLOWGRAPH, a .NET NativeAOT DLL first seen in the wild June 7, 2026, that uses Microsoft 365 calendar events via the Graph API as two-way dead drops dated May 13, 2050, with DNS tunneling refreshing Entra ID credentials. DarkAtlas also reported APT42's TAMECAT modular surveillance framework delivered via LNK masquerading as PDFs in spear-phishing targeting the nuclear energy sector in April-May 2026, with the group using generative AI to accelerate operations.

The Hacker News · 29d agoThreat actor

Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software TCP DNS Denial of Service Vulnerability

Cisco disclosed a TCP DNS flaw in ASA and FTD firewall software letting unauthenticated remote attackers trigger device reloads and denial of service.

A logic error in the DNS over TCP implementation of Cisco Secure Firewall ASA and FTD software mishandles buffer-size tracking when parsing DNS queries. An unauthenticated, remote attacker can send a crafted reply to a DNS query sent from the targeted device, causing the TCP DNS response handler to restart and the device to reload. The result is a denial of service condition on affected firewalls.

A rant about phishing: It's not the user's fault (and not DNS either)

Opinion piece argues multi-domain login redirects make legitimate flows indistinguishable from phishing, urging organizations to standardize on one recognizable root domain.

The author shows a real-world login flow that chains through numerous third-party domains (identity providers, cloud auth endpoints, OAuth APIs, 2FA pages), none on the company's own domain, so credentials and 2FA prompts are trivially impersonable. The piece argues URLs are inherently confusing because the security-relevant second-level domain sits mid-string, and that users trained to ignore URLs cannot distinguish legitimate pages from scams. It proposes RFC 2119-style requirements: single recognizable root domain, internal services on its subdomains, emailed or SMS links on that domain, and local redirects instead of third-party hosted pages.

Lobsters · security · 6d agoPhishing & fraud

xHunt Campaign: New PowerShell Backdoor Blocked Through DNS Tunnel Detection

xHunt's new CASHY200 PowerShell backdoor used DNS tunneling for C2; DNS security blocked beaconing at a Kuwait organization in September 2019.

Unit 42 describes CASHY200, a new PowerShell-based backdoor tied to the xHunt campaign that communicates with its C2 server windows64x[.]com via DNS tunneling, parsing commands from DNS answers. In September 2019, a Kuwait-based organization's DNS security service blocked the beaconing minutes after detection, cutting off adversary access. Samples dating to May and June 2018 and open source collection suggest the tool was used against Kuwait government organizations from spring 2018 through 2019, with malicious Word documents observed installing CASHY200 payloads configured with C2 domains such as firewallsupports[.]com and winx64-microsoft[.]com. The tool's name derives from identifiers stored under the registry key HKCU\Software\Microsoft\Cashe and the command value 200.

Palo Alto Unit 42 · Aug 17, 2026Threat actor

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

Project CAV3RN continues: Google Apps Script as C2 relay and DNS-based C2 channel selection

Project CAV3RN continues targeting Israel, using Google Apps Script C2 relays and DNS-based channel routing in a .NET NativeAOT framework.

Kaspersky Securelist documents the continuation of Project CAV3RN operations against Israel. The modular .NET NativeAOT framework uses Google Apps Script as a C2 relay and DNS-based C2 channel selection, blending command traffic with legitimate Google services to evade detection.

Kaspersky Securelist · Aug 11, 2026Threat actor in the wild

ZDI-26-584: dnsmasq DNSSEC NSEC/NSEC3 Type Bitmap Processing Infinite Loop Denial-of-Service Vulnerability

ZDI disclosed an unauthenticated infinite-loop denial-of-service flaw (CVE-2026-4890) in dnsmasq DNSSEC NSEC/NSEC3 bitmap processing.

The Zero Day Initiative published ZDI-26-584 describing an infinite loop in dnsmasq's processing of DNSSEC NSEC/NSEC3 type bitmaps. Remote unauthenticated attackers can trigger a denial-of-service condition on affected installations. ZDI assigned a CVSS score of 7.5 and the identifier CVE-2026-4890.

ZDI Published Advisories · Aug 13, 2026VulnerabilityCVE-2026-4890

ZDI-26-623: Linux Kernel IPv6 Multicast Routing Use-After-Free Local Privilege Escalation Vulnerability

ZDI-26-623 details a use-after-free in Linux kernel IPv6 multicast routing enabling local privilege escalation, rated CVSS 8.8.

The Zero Day Initiative published ZDI-26-623 describing a use-after-free vulnerability in the Linux kernel's IPv6 multicast routing implementation. A local attacker who can execute low-privileged code on an affected installation can exploit the flaw to escalate privileges. ZDI assigned a CVSS rating of 8.8; the advisory does not name a CVE id or state that exploitation has been observed.

ZDI Published Advisories · 7d agoAdvisory

The GNU C Library security advisory update for 2026-09-10

glibc advisory GLIBC-SA-2026-0016: nscd can crash from a stack overflow when an untrusted DNS server returns oversized responses.

A new GNU C Library advisory (GLIBC-SA-2026-0016) describes a stack overflow in the nscd service caused by unbounded alloca use. glibc 2.3.4 and newer may crash when a malicious DNS server returns an oversized response, resulting in degraded DNS resolution. Exploitation requires nscd to be enabled and the system to be using an untrusted DNS server. The advisory was posted to oss-security by glibc maintainer Siddhesh Poyarekar.

oss-securityupdated · 1d agofirst · 5d agoVulnerability 2 sources2

ZDI-26-683: Linux Kernel IPv6 VTI Subsystem Use-After-Free Local Privilege Escalation Vulnerability

ZDI discloses CVE-2026-72463, a CVSS 7.5 use-after-free in the Linux Kernel IPv6 VTI subsystem enabling privilege escalation.

ZDI-26-683 covers a use-after-free in the Linux Kernel IPv6 VTI subsystem that allows local attackers to escalate privileges. Exploitation requires first obtaining the ability to execute high-privileged code on the target system, limiting practical impact. ZDI assigned a CVSS rating of 7.5 and CVE-2026-72463.

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

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

The purpose of DNS is to spread scams

Interisle data cited by Terence Eden shows 8.5 million of 85 million new 2025 gTLD registrations blocklisted, implying a 10-20% scam domain abuse rate.

Terence Eden highlights statistics from an Interisle report on Domain Name System abuse. Of 85 million new gTLD registrations in 2025, 8.5 million were added to blocklists by May 2025, suggesting a 10% abuse floor that is likely closer to 20%. Eden calls the roughly one-in-five scam rate for newly registered gTLD domains a crisis and notes ICANN has discussed the problem for years.

Simon Willison · 10d agoPhishing & fraud

**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.

Hackers Disable Endpoint Protection and Deploy Sliver Across Compromised Windows Domain

The Hunter's Ledger tracked campaign UTA-2026-024 using Sliver C2, Domain Admin account creation, and Ethereum-based C2 rotation to compromise a US organization's Windows domain.

The Hunter's Ledger tracked an intrusion at one unnamed US organization as UTA-2026-024, staged from exposed server 193.233.202.17 with a Sliver beacon. Operators created a non-expiring Domain Admin account, enabled RDP with NLA disabled, dumped SAM, SYSTEM and SECURITY hives plus LSASS memory, and disabled eight endpoint protection services. A Node.js implant resolved its C2 server from an Ethereum smart contract that rotated domains five times in five months, while SYSTEM scheduled tasks with backdated dates and DNS allowlist manipulation provided persistence. The infrastructure ties to a confirmed ransomware incident, but no encryptor deployment was proven in this intrusion.

Cyber Security News · 8d agoThreat actor in the wild

Off Guard: Breaking LiteLLM from authentication bypass to cloud compromise

Wiz found LiteLLM auth bypass (CVE-2026-59822) and post-auth RCE (CVE-2026-59821) chainable to cloud compromise; the bypass is in CISA KEV with in-the-wild exploitation.

Wiz scanned roughly 3,074 internet-facing LiteLLM deployments and found 9.6% accepted the default master key sk-1234 or required no authentication, making post-auth attacks effectively pre-auth. The MCP endpoint accepts any Bearer token and grants a valid session (CVE-2026-59822), confirmed exploited in the wild via honeypots and added to CISA's Known Exploited Vulnerabilities catalog. Custom code guardrails allow post-auth root-level RCE via exec(compile(...)) (CVE-2026-59821), while pass-through endpoints lack URL validation, enabling cloud credential theft in post-auth scenarios. All assigned vulnerabilities have been patched; the research was presented at DEF CON 34.

Wiz Blog · 7d agoExploit / PoC in the wildCVE-2026-59822CVE-2026-598211

Unbound: 1.26.1 addresses multiple CVE items

Unbound 1.26.1 fixes critical heap buffer overflow CVE-2026-81642 in DNSKEY digesting that may allow remote code execution.

NLnet Labs released Unbound 1.26.1 on September 16 as a security release fixing several vulnerabilities, most notably CVE-2026-81642, rated CRITICAL, a heap buffer overflow during DNSKEY digesting that can possibly lead to remote code execution. Unbound is a widely deployed DNS recursive resolver and validating resolver. Administrators should upgrade promptly.