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USN-8742-1: Netty vulnerability

Ubuntu issues USN-8742-1 fixing a Netty DNS cache poisoning flaw caused by improper NS record bailiwick validation.

Ubuntu Security Notice USN-8742-1 addresses a vulnerability in the Netty framework in which NS records are incorrectly validated for bailiwick. An attacker could potentially exploit this to facilitate DNS cache poisoning attacks. Updated packages are available for supported Ubuntu releases.

Ubuntu Security Noticesupdated · 6h agofirst · 6d agoAdvisory 15 sources

[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

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.

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

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

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

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

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 · 2d agofirst · 6d agoVulnerability 2 sources2

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

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 · 13d agoVulnerability

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

Cloudflare DDoS Threat Report H1 2026: 1 Tbps attacks soar as DNS floods and geopolitical tensions drive a new wave

Cloudflare's H1 2026 report records a 519% surge in hyper-volumetric DDoS attacks, driven by DNS and CLDAP reflection amid geopolitical tensions.

Cloudflare detected a 519% surge in hyper-volumetric DDoS attacks across its network during the first half of 2026. Attack traffic was driven heavily by DNS and CLDAP reflection vectors, with 1 Tbps attacks becoming far more common. The report attributes reshaped attack patterns to major geopolitical conflicts.

Cloudflare Blog · Aug 11, 2026Research

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.

Cisco Security Advisories · 10h agoAdvisory 9 sources

CDN Tsunami Attack Abuses HTTP/3 Translation for Up to 350x DoS Amplification

Researchers disclosed two DoS attacks exploiting CDNs' HTTP/3-to-HTTP/1.1 translation to amplify low-bandwidth requests up to 350x against origin servers.

Researchers named the two techniques HTTP/3 Bandwidth Amplification (HBA) and HTTP/3 Connection Amplification (HCA), exploiting the gap where CDNs speak HTTP/3 to browsers but only HTTP/1.1 to origins. All six tested CDNs (Alibaba, Baidu, Cloudflare, CloudFront, Fastly, Tencent) were susceptible to HBA, and five to HCA, with Cloudflare immune to HCA because it buffers full requests before opening backend connections. Attackers using under 5 Mbps forced over 100 Mbps at origins, and the 350x factor applies only to Alibaba, Baidu, and Tencent, which support the QPACK dynamic table. Testing identified 42,330 potentially vulnerable subdomains out of 151,685 hosted on the six providers across the Tranco Top 1M.

The Hacker News · 27d agoResearch

Risky Bulletin: Russia starts blocking DoH and DoT

Russian users report blocks on DoH and DoT servers, including Cloudflare 1.1.1.1 and Google 8.8.8.8, in an apparent censorship crackdown.

Russian internet users began reporting failures connecting to DNS-over-HTTPS and DNS-over-TLS servers, suggesting a government crackdown on the two privacy protocols. The blocks reportedly cover Cloudflare's 1.1.1.1 and Google's 8.8.8.8 resolvers; Roskomnadzor has not officially confirmed the action. The agency tested a similar block in March on Beeline's network and had named DoH for blocking as early as 2021. The bulletin also briefly notes state-sponsored phishing of EU officials, a DDoS against Norway's Digdir, the ReliaQuest/ShinyHunters dispute, and older ransomware and breach disclosures.

Risky Business News · 21d agoPolicy & legal1

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.

oss-security · 11h agoVulnerabilityCVE-2026-81642

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

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

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

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

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

USN-8730-1: Linux kernel vulnerability

Ubuntu issued USN-8730-1 fixing Linux kernel flaws in IPv6 networking and Netfilter that could allow system compromise.

Ubuntu released USN-8730-1 addressing a security issue discovered in the Linux kernel. The update corrects flaws in the IPv6 networking and Netfilter subsystems. Ubuntu states an attacker could possibly use the issue to compromise the system.

Ubuntu Security Notices · 9d agoAdvisory 6 sources

Heap overflow in kernel driver due to missing size validation

Fortinet fixes a CVSS 7.3 heap overflow in the FortiClient Windows kernel driver enabling code execution via crafted DNS responses.

Fortinet PSIRT advisory FG-IR-26-156, revised 2026-08-12, describes a heap-based buffer overflow (CWE-120, buffer copy without checking input size) in the FortiClient Windows kernel driver, scored CVSSv3 7.3. An unauthenticated attacker positioned to alter or craft DNS responses for a targeted host could execute arbitrary code via malicious packets. No CVE identifier or exploitation status is provided in the advisory text, so administrators should check the full bulletin for affected versions and fixed releases.

Fortinet PSIRT · Aug 12, 2026Advisory

ZDI-26-710: NoMachine mDNS Heap-based Buffer Overflow Remote Code Execution Vulnerability

ZDI disclosed CVE-2026-92208, an unauthenticated heap-based buffer overflow in NoMachine's mDNS service enabling network-adjacent remote code execution (CVSS 8.8).

ZDI published advisory ZDI-26-710 describing a heap-based buffer overflow vulnerability in NoMachine's mDNS service, tracked as CVE-2026-92208 with CVSS 8.8. Network-adjacent attackers can execute arbitrary code on affected installations without authentication. The advisory does not mention observed exploitation or patch availability.

DDoS Attack Hits Norwegian Government Services

A coordinated DDoS campaign disrupted Norwegian government online services, causing availability outages across public digital services.

A coordinated distributed denial-of-service campaign caused disruption to Norwegian government digital services, according to Infosecurity Magazine. The attack affected the availability of public-facing services, and no data compromise was indicated in initial reporting. The responsible group or motive was not named in the report.

Infosecurity Magazine · 21d agoThreat actor

September 2026 Patch Tuesday roundup: Plugs for two zero day holes among almost 1,000 fixes in Windows

Microsoft's September 2026 Patch Tuesday ships 964 fixes including two exploited Windows zero-days (CVE-2026-85880, CVE-2026-81963) and a wormable DNS RCE.

Microsoft's September 2026 Patch Tuesday includes 964 Microsoft vulnerabilities requiring customer action, a record attributed to AI-assisted bug discovery, plus 174 third-party/open-source and 23 Chromium/Edge CVEs. Two zero-days are exploited in the wild: CVE-2026-85880, a Windows ALPC heap overflow enabling AppContainer sandbox escape and privilege escalation, and CVE-2026-81963, a Windows Update Stack escalation to SYSTEM. CVE-2026-69730, an unauthenticated Windows DNS RCE, is not yet exploited but Microsoft expects exploitation, and roughly 20 bugs could be wormable. Separately, SAP issued a critical CVSS 10.0 fix for the EPP component used in S/4HANA and NetWeaver.

CSO Online · 7d agoVulnerability in the wildCVE-2026-85880CVE-2026-81963CVE-2026-69730+2 CVEs1

CVE-2026-82439: Apache Storm DRPC: Unauthenticated Unbounded Memory Growth in DRPC

Unauthenticated DRPC requests to Apache Storm 3.0.0 cause unbounded memory growth in the function-name queue map, enabling DoS.

CVE-2026-82439 (severity: important) affects Apache Storm DRPC (storm-server) versions 3.0.0 before 3.1.0. The DRPC server maintained a map from function name to request queue, creating an entry on first sight of a name, but no code path ever removed entries: request cleanup removed requests from queues but the queue objects and map entries persisted. An unauthenticated attacker could send requests for arbitrary function names to drive unbounded memory growth and crash the server.

oss-security · 3d agoVulnerabilityCVE-2026-82439