ZeroHour

Search: “dnssec”

28 stories

Smart search ranks by meaning as well as keywords (one row per story, last 45 days).

CVE-2026-76461: Critical Cisco Secure Email Gateway Vulnerability Exploited in the Wild

Cisco Secure Email Gateway zero-day CVE-2026-76461 (CVSS 9.8) enables unauthenticated root command execution via crafted email; CISA added it to KEV.

CVE-2026-76461 is a critical SQL injection (CVSS 9.8) in Cisco AsyncOS for Secure Email Gateway allowing an unauthenticated remote attacker to execute arbitrary commands with root privileges by sending a specially crafted email through a vulnerable gateway. CISA added it to the KEV catalog on disclosure day, indicating zero-day exploitation, and Cisco PSIRT became aware of active exploitation in September 2026. No public PoC or attribution exists; fixed versions are 15.5.5-014, 16.0.4-302, and 16.5.0-780, and admins should check mail_logs for suspicious SQL statements like 'COPY.*TO PROGRAM'.

Rapid7 Blogupdated · 8h agofirst · 1d agoExploit / PoC in the wild 17 sourcesCVE-2026-76461

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

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

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.

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

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

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

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

What your vendor says about PQC tells you if they are ready

Allot CTO outlines a telecom post-quantum migration playbook: inventory crypto, deploy hybrid ML-KEM on TLS first, and avoid missed interfaces.

Dr. Yaakov Stein, VP CTO of Allot, explains how mobile operators should triage post-quantum migration by data shelf life, protecting subscriber identity mappings, billing records, and call metadata that stay sensitive for years. He recommends starting with a comprehensive crypto inventory, then hybrid ML-KEM key exchange on TLS-protected 5G SBA and management interfaces, followed by IPsec backhaul and roaming links. Stein warns that migrations most often fail operationally through missed legacy interfaces such as SSH, RADIUS, or forgotten load balancers, and cites the early Kyber multi-packet TLS client hello issue as an example of middlebox incompatibility.

Help Net Security · 15d 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

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 · 5d agoVulnerability 2 sources2

[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

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

ISC has disclosed fourteen vulnerabilities in BIND 9 (CVE-2026-19033, CVE-2026-19662, CVE-2026-19666, CVE-2026-19667, CVE-2026-19668, CVE-2026-19941, CVE-2026-75029, CVE-2026-76163, CVE-2026-77119, CVE-2026-77692, CVE-2026-78301, CVE-2026-80274, CVE-2026-81563, CVE-2026-81736)

ISC discloses fourteen vulnerabilities in BIND 9 DNS software, including a use-after-free, with fixes now available.

On September 16, 2026, Internet Systems Consortium disclosed fourteen vulnerabilities affecting BIND 9, listing CVE-2026-19033, CVE-2026-19662, CVE-2026-19666 (use-after-free), CVE-2026-19667, CVE-2026-19668, CVE-2026-19941, CVE-2026-75029, CVE-2026-76163, CVE-2026-77119, CVE-2026-77692, CVE-2026-78301, CVE-2026-80274, CVE-2026-81563, and CVE-2026-81736. Details and fixes are published in the ISC knowledge base. No active exploitation is reported in the announcement.

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

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

Orthanc DICOM Server

CISA advisory flags CVE-2026-87020, an integer overflow in Orthanc DICOM Server <1.13.0 causing heap out-of-bounds write and denial of service when decoding crafted PNG/JPEG images.

CISA published ICSMA-26-253-02 for Orthanc DICOM Server versions below 1.13.0, used in healthcare environments worldwide. CVE-2026-87020 (CWE-190) is an integer overflow in pitch and buffer-size computation causing a heap out-of-bounds write when decoding attacker-supplied PNG or JPEG images. An authenticated remote attacker can crash the Orthanc process and cause denial of service; CVSS v3.1 is 8.1 HIGH. CISA states no known public exploitation targeting this flaw has been reported.

CISA Advisories · 6d agoAdvisoryCVE-2026-87020

CVE-2026-19490: Critical Vulnerability Affecting Citrix NetScaler ADC and NetScaler Gateway

CVE-2026-19490 is a critical unauthenticated authentication bypass in Citrix NetScaler ADC and Gateway, remotely exploitable without user interaction.

An advisory published August 19, 2026 describes CVE-2026-19490, a critical authentication bypass affecting Citrix NetScaler ADC and NetScaler Gateway. The flaw carries a CVSS v4.0 base score of 9.3 and is remotely exploitable by unauthenticated attackers over the network without user interaction or elevated privileges. NetScaler ADC and Gateway are widely deployed enterprise products positioned at or near the network perimeter, providing load balancing, SSL/TLS offloading, and secure remote access. The text does not state whether exploitation has been observed in the wild.

Rapid7 Blog · 28d agoVulnerabilityCVE-2026-194901

Hackers Steal Active Directory Password Hashes Without Attacking Domain Controllers Directly

Attackers use the DCSync technique to impersonate domain controllers and harvest AD password hashes and Kerberos keys without directly compromising domain controllers, Trellix warns.

Per Trellix, threat actors increasingly abuse Active Directory replication via DCSync, using privileged credentials to invoke DRSGetNCChanges and retrieve NTLM password hashes and Kerberos key material without running code on domain controllers. Capturing the krbtgt account hash enables forging Golden Tickets for persistent, highly privileged domain access. Because malicious replication traffic mimics legitimate DRS/RPC activity, defenders should monitor Windows Security Event ID 4662, restrict replication permissions, and investigate replication requests from non-domain-controller systems.

GBHackers · 6d agoResearch in the wild 2 sources2

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

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.

WebPros security advisory (AV26-866)

Canada's Cyber Centre relays a WebPros advisory for CVE-2026-67394, a Plesk privilege escalation flaw to root, fixed in 18.0.79.9 and 18.0.80.5.

The Canadian Centre for Cyber Security issued alert AV26-866 relaying WebPros' security advisory for Plesk. CVE-2026-67394 allows privilege escalation to root and affects Plesk versions prior to 18.0.79.9 and 18.0.80.5. Administrators are encouraged to review the advisory and apply the available updates.

Cisco FMC CVE-2026-20079 Actively Exploited

Cisco confirms active exploitation of CVE-2026-20079, a maximum-severity authentication bypass in Secure Firewall Management Center.

Cisco has confirmed that CVE-2026-20079, a critical authentication bypass in Cisco Secure Firewall Management Center (FMC), is being actively exploited in the wild. The vulnerability carries a maximum CVSS severity, and defenders are urged to treat it as an urgent patch priority. FMC centrally manages Cisco Secure Firewall deployments, so exposure across enterprise environments is likely.

SOCRadarupdated · 2d agofirst · 6d agoExploit / PoC in the wild 9 sourcesCVE-2026-20079

Dutch NCSC: Critical Check Point VPN flaws exploitation is imminent

Dutch NCSC warns exploitation is imminent for critical Check Point VPN RCE flaws CVE-2026-85102 and CVE-2026-85103, urging immediate patching of Security Gateways.

The Dutch NCSC assesses the likelihood and impact of exploitation as high for two critical Check Point VPN flaws, though no public PoC exploit has been reported. CVE-2026-85102 is improper validation of certificate data during VPN negotiation, and CVE-2026-85103 is a heap overflow in the VPN certificate ASN.1 decoder; both enable remote code execution on Security Gateways, the latter also on Security Management Servers. Affected releases span R81.20, R82, R82.10, R81.10.x, R82.00.x and EoS versions R80 through R81.10, while R82.20 is unaffected. Check Point shipped fixes on September 9 via LivePatch Take 24 and Jumbo Hotfix Accumulator takes, and NCSC advises restricting Site-to-Site VPN rules to trusted IPs.

BleepingComputerupdated · 5h agofirst · 4d agoVulnerability 9 sourcesCVE-2026-85102CVE-2026-851032

Active exploitation of Cisco Secure Firewall Management Center vulnerabilities

Cisco Talos reports in-the-wild exploitation of critical FMC flaw CVE-2026-20079 by three clusters including a Sandworm-linked APT and Qilin ransomware affiliates.

Cisco Talos is tracking active exploitation of CVE-2026-20079 (CVSS 10.0), an authentication bypass in Cisco Secure Firewall Management Center that lets unauthenticated remote attackers execute scripts and obtain root access, and CVE-2026-20316 (CVSS 5.3), which permits low-privileged logins and can be chained for privilege escalation. Talos identified three post-compromise clusters: UAT-12197 deploying JSP web shells and a JAR command executor for credential theft; UAT-11823, an APT overlapping with Sandworm, deploying a Netcat reverse shell and Cyclops Blink malware; and UAT-11988, assessed as a ransomware operator with TTPs consistent with Qilin affiliates. Hotfixes are available, with a comprehensive hardening release due the week of September 14, 2026.

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

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

ZDI-26-622: Microsoft Windows IKEv2 AES-GCM Decryption Integer Underflow Remote Code Execution Vulnerability

ZDI disclosed CVE-2026-50696, a CVSS 8.1 integer underflow in Windows IKEv2 AES-GCM decryption enabling unauthenticated remote code execution on specific IPsec configurations.

The Zero Day Initiative published ZDI-26-622 describing a remote code execution vulnerability in Microsoft Windows' IKEv2 AES-GCM decryption path, caused by an integer underflow. Authentication is not required for exploitation, but only systems using specific IPsec configurations are affected. ZDI assigned the vulnerability a CVSS score of 8.1 and the identifier CVE-2026-50696.