All news with #cisco tag

PolarEdge Botnet Targets Cisco, ASUS, QNAP Routers

🔐 Cybersecurity researchers have detailed PolarEdge, a TLS-based ELF implant used to conscript Cisco, ASUS, QNAP and Synology routers into a botnet. The backdoor implements an mbedTLS v2.8.0 server with a custom binary protocol, supports a connect-back and interactive debug mode, and stores its obfuscated configuration in the final 512 bytes of the ELF. Operators use anti-analysis techniques, process masquerading and file-moving/deletion routines; a forked watchdog can relaunch the payload if the parent process disappears.

Legacy Flaws in Network Edge Devices Threaten Orgs Today

🔒 Enterprises' network edge devices — firewalls, VPNs, routers, and email gateways — are increasingly being exploited due to longstanding 1990s‑era flaws such as buffer overflows, command and SQL injections. Researchers tracked dozens of zero‑day exploits in 2024 and continuing into 2025 that affected vendors including Fortinet, Palo Alto Networks, Cisco, Ivanti, and others. These appliances are attractive targets because they are remotely accessible, often lack endpoint protections and centralized logging, and hold privileged credentials, making them common initial access vectors for state‑affiliated actors and ransomware groups.

Zero Disco: Fileless Rootkits Target Legacy Cisco Switches

⚠️Threat actors exploited a Cisco SNMP vulnerability (CVE-2025-20352) to achieve remote code execution on legacy IOS XE switches and install custom, largely fileless Linux rootkits that hook into the IOSd memory space, set universal passwords (including one containing 'Disco'), and hide processes and network activity. The rootkits spawn a UDP-based controller to toggle or zero logs, bypass access controls, and reset running-config timestamps to mask changes. Trend Micro also observed spoofed IP/MAC addresses and attempts to combine a retooled Telnet memory-access exploit to deepen persistence.

Hackers Deploy Rootkit via Cisco SNMP Zero-Day on Switches

⚠️Threat actors exploited a recently patched SNMP remote code execution flaw (CVE-2025-20352) in older Cisco IOS and IOS XE devices to deploy a persistent Linux rootkit. Trend Micro reports the campaign targeted unprotected 9400, 9300 and legacy 3750G switches and has been tracked as Operation Zero Disco, named for the universal password that contains 'disco'. The implant can disable logging, bypass AAA and VTY ACLs, hide running-configuration items and enable lateral movement; researchers recommend low-level firmware and ROM-region checks when compromise is suspected.

Cisco SNMP Rootkit Campaign Targets Network Devices

🔒 Trend Micro detailed a campaign exploiting CVE-2025-20352 that installed Linux rootkits on exposed Cisco switches and routers, enabling persistent unauthorized access. The attackers combined an SNMP remote code execution with a modified Telnet flaw (based on CVE-2017-3881) to read and write device memory and deploy fileless backdoors. Affected models include Cisco 9400, 9300 and legacy 3750G series. Device owners should apply Cisco patches, disable or harden SNMP and restrict management access.

Attackers Use Cisco SNMP Flaw to Deploy Linux Rootkits

🛡️ Researchers disclosed a campaign, Operation Zero Disco, that exploited a recently patched SNMP stack overflow (CVE-2025-20352) in Cisco IOS and IOS XE devices to deploy Linux rootkits on older, unprotected switches. The attackers achieved remote code execution and persistence by installing hooks into IOSd memory and setting universal passwords that include the string "disco." Targets included legacy 3750G and 9300/9400 series devices lacking EDR protections.

Leading Incident Response Through Empathy and Care

🛡️ Laura Faria, an incident commander with Cisco Talos Incident Response, discusses leading through chaos, empathy, and teamwork during high-pressure security incidents. She traces a career across multiple cybersecurity vendors and sales roles before joining Talos and stepping into incident command. Laura emphasizes purpose-driven response work, particularly when outages affect critical infrastructure and patient safety. The interview highlights resilience, collaboration, and practical leadership lessons.

Rockwell Stratix Devices Vulnerable to SNMP Stack Overflow

⚠️ Rockwell Automation has published an advisory for Stratix switches informing operators of a stack-based buffer overflow in the SNMP subsystem derived from Cisco IOS XE (CVE-2025-20352). A remote, authenticated attacker with knowledge of SNMPv2c read-only community strings or valid SNMPv3 credentials could cause a denial-of-service, while administrative (privilege 15) credentials may permit arbitrary code execution as root. Affected models include Stratix 5700, 5400, 5410, 5200, and 5800; Rockwell and CISA recommend applying Cisco workarounds, implementing network isolation, using secure remote access, and following Rockwell advisory SD1749.

Rockwell Automation Lifecycle Services SNMP Overflow

⚠️ Rockwell Automation reports a stack-based buffer overflow in its Lifecycle Services with Cisco offerings related to the Cisco IOS XE SNMP subsystem (CVE-2025-20352). An authenticated remote actor with low privileges can trigger a denial-of-service, and an actor with higher privileges and administrative access may achieve arbitrary code execution as root. A CVSS v4 score of 6.3 and a CVSS v3 score of 7.7 are provided. Rockwell and Cisco publish updates and mitigations; CISA advises minimizing network exposure and applying vendor fixes or recommended workarounds.

How to Respond After Clicking a Suspicious Link Safely

⚠ If you clicked a suspicious link, stay calm and act promptly. For work devices, contact IT immediately and follow their instructions. For personal devices, close the browser and check for unexpected downloads; if you entered credentials, change passwords and enable MFA; if financial data was entered, contact your bank; if a file was downloaded, disconnect, run a full scan, and consider restoring from a clean backup. Monitor accounts and report phishing attempts.

Hidden Text Salting: CSS Abuse in Email Threats and Evasion

🧂 Cisco Talos documents growing abuse of CSS to insert visually hidden 'salt' into emails, a technique that undermines parsing and language-detection systems. Observed across preheaders, headers, attachments and bodies between March 1, 2024 and July 31, 2025, attackers use CSS properties (font-size, opacity, display, clipping) and zero-width characters to conceal irrelevant content. Talos recommends detection plus HTML sanitization and filters—examples include Cisco Secure Email Threat Defense—to strip or ignore invisible content before downstream analysis.

Palo Alto Login Portal Scanning Spikes 500% Globally

🔍 Security researchers observed a roughly 500% surge in reconnaissance activity targeting Palo Alto Networks login portals on October 3, when GreyNoise recorded about 1,300 unique IP addresses probing its Palo Alto Networks Login Scanner tag versus typical daily volumes under 200. Approximately 91% of the IPs were US-based and 93% were classed as suspicious, with 7% confirmed malicious. GreyNoise also reported parallel scanning of other remote-access products including Cisco ASA, SonicWall, Ivanti and Pulse Secure, and noted shared TLS fingerprinting and regional clustering tied to infrastructure in the Netherlands. Analysts will continue monitoring for any subsequent vulnerability disclosures.

Spike in Scanning Targets Palo Alto Login Portals Globally

🔍 GreyNoise observed a nearly 500% surge in IP addresses scanning Palo Alto Networks login portals on October 3, 2025, jumping from about 200 to roughly 1,300 unique IPs. The firm classified 93% of those IPs as suspicious and 7% as malicious, with most activity geolocated to the U.S. and smaller clusters in the U.K., the Netherlands, Canada and Russia. GreyNoise noted the traffic was targeted and structured and shared a dominant TLS fingerprint with recent Cisco ASA scans.

UAT-8099 Targets High-Value IIS Servers for SEO Fraud

🔍 Cisco Talos details UAT-8099, a Chinese-speaking cybercrime group that compromises reputable IIS servers to conduct SEO fraud and steal high-value credentials, certificates and configuration files. The actors exploit file-upload weaknesses to deploy ASP.NET web shells, enable RDP, create hidden administrative accounts and install VPN/reverse-proxy tools for persistence. They automate operations with custom scripts, deploy Cobalt Strike via DLL sideloading and install multiple BadIIS variants to manipulate search rankings and redirect mobile users to ads or gambling sites. Talos published IoCs, Snort/ClamAV signatures and mitigation guidance.

Nearly 50,000 Cisco Firewalls Exposed to Active Flaws

⚠️More than 48,800 internet-exposed Cisco ASA and FTD appliances remain vulnerable to two remotely exploitable flaws, CVE-2025-20333 and CVE-2025-20362, that allow arbitrary code execution and access to restricted VPN endpoints. Cisco confirmed active exploitation began before patches were available and no workarounds exist. Administrators should restrict VPN web interface exposure, increase logging and monitoring for suspicious VPN activity, and apply vendor fixes immediately.

CISA Adds Five Vulnerabilities to KEV Catalog; Federal Risk

⚠️ CISA added five vulnerabilities to its Known Exploited Vulnerabilities (KEV) Catalog on Sept. 29, 2025, citing evidence of active exploitation. The newly listed issues are CVE-2021-21311 (Adminer SSRF), CVE-2025-20352 (Cisco IOS/IOS XE stack overflow), CVE-2025-10035 (Fortra GoAnywhere deserialization), CVE-2025-59689 (Libraesva command injection), and CVE-2025-32463 (sudo untrusted-control vulnerability). Federal Civilian Executive Branch agencies must remediate these under BOD 22-01, and CISA urges all organizations to prioritize timely fixes as part of standard vulnerability management.

September 2025 Zero-Day Exploits Impact Cisco ASA/FTD

⚠️ Cisco reported active exploitation of multiple zero-day vulnerabilities in ASA and FTD software by a state-sponsored actor tracked as ArcaneDoor. Two CVEs (CVE-2025-20333 and CVE-2025-20362) are being exploited in the wild and a third (CVE-2025-20363) is at high risk for imminent exploitation. Cisco released updates on Sep. 25, 2025, and CISA issued Emergency Directive 25-03; organizations should prioritize immediate patching or apply vendor mitigations when updates are not yet possible.

ArcaneDoor Targets Cisco ASA Firewalls in New Campaign

🔒 Cisco has linked a renewed campaign exploiting Cisco ASA 5500-X devices to the espionage-focused ArcaneDoor threat actor. The operation leveraged zero-day flaws, notably CVE-2025-20333 and CVE-2025-20362, to implant malware, modify ROMMON for persistence and evade detection by disabling logging and intercepting CLI commands. Observed compromises affected older ASA models lacking Secure Boot/Trust Anchor protections; Cisco and national authorities urge immediate remediation. Temporary mitigations include disabling SSL/TLS VPN web services and IKEv2 client services while applying vendor fixes and conducting forensics.

Cisco ASA Zero-Days Enable Bootkit and Loader Attacks

🛡️ The U.K. NCSC and Cisco confirmed active exploitation of recently disclosed vulnerabilities in Cisco Secure Firewall ASA devices that allowed deployment of previously undocumented malware families, notably RayInitiator and LINE VIPER. Cisco traced attacks beginning in May 2025 that targeted ASA 5500‑X appliances (running ASA 9.12/9.14 with VPN web services enabled), using multiple zero-day flaws to bypass authentication and execute code. Attackers employed a persistent GRUB bootkit, ROMMON modifications on non‑Secure Boot platforms, and extensive evasion techniques — disabling logging, intercepting CLI, and crashing devices — to maintain stealth and persistence. Organizations are urged to apply vendor fixes, migrate off end‑of‑support models, and monitor for indicators of compromise.

Critical Cisco Firewall Zero-Day Demands Immediate Patch

🔴 A critical zero-day vulnerability (CVE-2025-20363) in Cisco firewall and IOS families requires immediate patching, US CISA and the UK NCSC warned. Cisco says the flaw is caused by improper validation of user-supplied HTTP input and can allow remote arbitrary code execution as root when exploited. Affected products include Cisco Secure Firewall ASA, FTD, and certain IOS/IOS XE/IOS XR builds; Cisco has released fixes and advises there are no viable workarounds.