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Exploitation of PAN-OS Captive Portal Zero-Day for Unauthenticated Remote Code Execution ![Clock Icon](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-clock.svg) 5 min read Related Products [![Advanced DNS Security icon](https://unit42.paloaltonetworks.com/wp-content/uploads/2024/06/strata_RGB_logo_Icon_Color.png)Advanced DNS Security](https://unit42.paloaltonetworks.com/product-category/advanced-dns-security/ "Advanced DNS Security")[![Advanced Threat Prevention icon](https://unit42.paloaltonetworks.com/wp-content/uploads/2024/06/strata_RGB_logo_Icon_Color.png)Advanced Threat Prevention](https://unit42.paloaltonetworks.com/product-category/advanced-threat-prevention/ "Advanced Threat Prevention")[![Advanced URL Filtering icon](https://unit42.paloaltonetworks.com/wp-content/uploads/2024/06/strata_RGB_logo_Icon_Color.png)Advanced URL Filtering](https://unit42.paloaltonetworks.com/product-category/advanced-url-filtering/ "Advanced URL 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![Published Icon](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-calendar-grey.svg) Published:May 6, 2026 * ![Tags Icon](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-category.svg) Categories: * [High Profile Threats](https://unit42.paloaltonetworks.com/category/top-cyberthreats/) * [Vulnerabilities](https://unit42.paloaltonetworks.com/category/vulnerabilities/) * ![Tags Icon](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-tags-grey.svg) Tags: * [CVE-2026-0300](https://unit42.paloaltonetworks.com/tag/cve-2026-0300/) * [EarthWorm](https://unit42.paloaltonetworks.com/tag/earthworm/) * [PAN-OS](https://unit42.paloaltonetworks.com/tag/pan-os/) * [Remote Code Execution](https://unit42.paloaltonetworks.com/tag/remote-code-execution/) * [ReverseSocks5](https://unit42.paloaltonetworks.com/tag/reversesocks5/) * [Vulnerability](https://unit42.paloaltonetworks.com/tag/vulnerability/) * [Zero-day](https://unit42.paloaltonetworks.com/tag/zero-day/) * [![Download Icon](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-download.svg)](https://unit42.paloaltonetworks.com/captive-portal-zero-day/?pdf=download&lg=en&_wpnonce=48697d1bdd "Click here to download") * [![Print Icon](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-print.svg)](https://unit42.paloaltonetworks.com/captive-portal-zero-day/?pdf=print&lg=en&_wpnonce=48697d1bdd "Click here to print") Share![Down arrow](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/down-arrow.svg) * ![Link Icon](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-share-link.svg) * [![Link 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Vulnerable systems allow an unauthenticated attacker to execute arbitrary code with root privileges on the PA-Series and VM-Series firewalls by sending specially crafted packets. We are aware of only limited exploitation of CVE-2026-0300 at this time. Unit 42 is tracking CL-STA-1132, a cluster of likely state-sponsored threat activity exploiting CVE-2026-0300. The attacker behind this activity exploited CVE-2026-0300 to achieve unauthenticated remote code execution (RCE) in PAN-OS software. Upon successful exploitation, the attacker was able to inject shellcode into an nginx worker process. Post-exploitation activity includes deployment of publicly available tunneling tools (EarthWorm, ReverseSocks5), Active Directory enumeration using credentials likely obtained from the firewall, and the systematic destruction of logs and other evidence of compromise. Palo Alto Networks[Cortex Xpanse](https://docs-cortex.paloaltonetworks.com/p/XPANSE) can identify exposed instances of the User-ID Authentication Portal potentially vulnerable to CVE-2026-0300. Palo Alto Networks customers receive protections from and mitigations in the following products: * [Advanced WildFire](https://docs.paloaltonetworks.com/wildfire) * [Next-Generation Firewall](https://docs.paloaltonetworks.com/ngfw) with [Advanced Threat Prevention](https://docs.paloaltonetworks.com/advanced-threat-prevention/administration) * [Advanced URL Filtering](https://docs.paloaltonetworks.com/pan-os/10-1/pan-os-new-features/url-filtering-features/advanced-url-filtering) and [Advanced DNS Security](https://docs.paloaltonetworks.com/dns-security) * [Cortex AgentiX](https://www.paloaltonetworks.com/cortex/agentix) * [Cortex Xpanse](https://docs-cortex.paloaltonetworks.com/p/XPANSE) The [Unit 42 Incident Response team](https://start.paloaltonetworks.com/contact-unit42.html) can also be engaged to help with a compromise or to provide a proactive assessment to lower your risk. |-------------------------------|-------------------| | **Vulnerabilities Discussed** | **CVE-2026-0300** | ## Details of the Vulnerability A buffer overflow vulnerability in the User-ID Authentication Portal (aka Captive Portal) service of Palo Alto Networks PAN-OS software allows an unauthenticated attacker to execute arbitrary code with root privileges on the PA-Series and VM-Series firewalls by sending specially crafted packets through network traffic. While Prisma Access, Cloud NGFW and Panorama appliances remain unaffected by this vulnerability, the risk of unauthenticated RCE exploitation is significantly elevated when the User-ID Authentication Portal is exposed to the public internet or untrusted networks. Adhering to best practice guidelines by restricting User-ID Authentication Portal access exclusively to trusted internal IP addresses and ensuring the portal is not publicly reachable will greatly mitigate this risk. ## Current Scope of the Attack Using CVE-2026-0300 We are aware of only limited exploitation of CVE-2026-0300 at this time. Starting April 9, 2026, there were unsuccessful exploitation attempts against a PAN-OS device. A week later, the attackers successfully achieved RCE against the device and injected shellcode. Following the compromise, the attackers immediately conducted log cleanup to mitigate detection by clearing crash kernel messages, deleting nginx crash entries and nginx crash records, as well as removing crash core dump files. The attackers deployed a number of tools with root privileges four days later, before conducting Active Directory (AD) enumeration using the firewall's service account credentials to target domain root and [DomainDnsZones](https://learn.microsoft.com/en-us/windows-server/identity/ad-ds/plan/active-directory-integrated-dns-zones). Following enumeration, the attackers deleted [ptrace](https://man7.org/linux/man-pages/man2/ptrace.2.html) injection evidence from the audit log and deleted the SetUserID (SUID) privilege escalation binary. On April 29, 2026, the attackers conducted a Security Assertion Markup Language (SAML) flood against the previously targeted device, which promoted a second device to Active, inheriting the same internet-facing traffic. RCE was then achieved on the second device, where EarthWorm and ReverseSocks5 were downloaded. ### EarthWorm Earthworm is an [open-source](https://github.com/rootkiter/EarthWorm) network tunneling tool written in C that operates on Windows, Linux, macOS and ARM/MIPS-based platforms. It functions as a SOCKS v5 server and port transfer utility designed to establish covert communication channels across restricted network boundaries. Earthworm capabilities include: * Initiates a forward SOCKS5 server to proxy incoming connections (MITRE ATT\&CK technique [T1090](https://attack.mitre.org/techniques/T1090/)). * Establishes reverse SOCKS5 tunnels from internal hosts to external attacker-controlled bridges (T1090). * Bridges data between two separate listening ports to facilitate pivot management (T1090). * Forwards traffic from a local port to a remote destination host and port (T1090). * Chains multiple transfer modes to create multi-hop cascaded network tunnels ([T1572](https://attack.mitre.org/techniques/T1572/)). * Encapsulates traffic for protocols like RDP and SSH within SOCKS tunnels (T1572). EarthWorm has reportedly been used by the threat actor behind [CL-STA-0046](https://unit42.paloaltonetworks.com/rare-possible-gelsemium-attack-targets-se-asia), [Volt Typhoon](https://media.defense.gov/2023/May/24/2003229517/-1/-1/0/CSA_Living_off_the_Land.PDF), [UAT-8337](https://blog.talosintelligence.com/uat-8837) and [APT41](https://www.trendmicro.com/en_us/research/22/k/hack-the-real-box-apt41-new-subgroup-earth-longzhi.html). ### ReverseSocks5 ReverseSocks5 is an open-source networking tool used to bypass firewalls or NAT by establishing an outbound connection from a target machine to a controller, rather than the other way around. Once the connection is established, it creates a SOCKS5 proxy tunnel that allows the controller to route traffic into the target's internal network. Because the source code is publicly available, it is frequently utilized by system administrators for remote management, and also by threat actors for pivoting during a breach. ## Interim Guidance Customers can mitigate the risk of this issue by taking either of the following actions: * Restrict User-ID Authentication Portal access to only trusted zones and in addition, disable Response Pages in the Interface Management Profile attached to every L3 interface in any zone where untrusted/internet traffic can ingress. Keep Response Pages enabled only on interfaces in trust/internal zones where legitimate users' browsers ingress. Refer to Step 6 of the linked [Live Community article](https://live.paloaltonetworks.com/t5/general-articles/why-it-s-essential-to-secure-your-management-interface/ta-p/1001286) and [Knowledgebase article](https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA14u000000CqbiCAC) for steps to restrict access. * Disable User-ID Authentication Portal if not required. Customers with an Advanced Threat Prevention subscription can block attacks for this vulnerability by enabling Threat ID 510019 from Applications and Threats content version 9097-10022. Decoder capabilities necessitate PAN-OS 11.1 or a later version for Threat ID support. Palo Alto Networks recommends following guidance in the [security advisory](https://security.paloaltonetworks.com/CVE-2026-0300). ## Conclusion Over the last five years, nation-state threat actors engaged in cyber espionage have increasingly focused their efforts on [edge-network](https://www.cisa.gov/news-events/cybersecurity-advisories/aa26-113a#:~:text=The%20edge%20devices%20were%20vulnerable,security%20patches%20by%20their%20manufacturers.) technological assets, including [firewalls](https://www.cisa.gov/news-events/cybersecurity-advisories/aa25-239a), [routers](https://securityscorecard.com/blog/threat-intelligence-research-volt-typhoon/), [IoT devices](https://cloud.google.com/blog/topics/threat-intelligence/unc3524-eye-spy-email), [hypervisors](https://cloud.google.com/blog/topics/threat-intelligence/esxi-hypervisors-malware-persistence) and various [VPN solutions](https://unit42.paloaltonetworks.com/shadow-campaigns-uncovering-global-espionage/#:~:text=Executive%20Summary,that%20operates%20out%20of%20Asia.), which provide high-privilege access while often lacking the robust logging and security agents found on standard endpoints. The reliance of the attackers behind CL-STA-1132 on open-source tooling, rather than proprietary malware, minimized signature-based detection and facilitated seamless environment integration. This technical choice, combined with a disciplined operational cadence of intermittent interactive sessions over a multi-week period, intentionally remained below the behavioral thresholds of most automated alerting systems. The lateral movement technique prioritized identity trust abuse over traditional network-layer pivoting, effectively reducing the attacker's footprint. Consequently, this campaign demonstrates that operational restraint---specifically the use of non-persistent access windows---is a primary factor in maintaining long-term residency on edge infrastructure. Palo Alto Networks has shared our findings with our fellow Cyber Threat Alliance (CTA) members. CTA members use this intelligence to rapidly deploy protections to their customers and to systematically disrupt malicious cyber actors. Learn more about the [Cyber Threat Alliance](https://www.cyberthreatalliance.org/). Palo Alto Networks customers are better protected by our products, as listed below. We will update this threat brief as more relevant information becomes available. ## Palo Alto Networks Product Protections for Exploitation of PAN-OS Captive Portal Zero-Day for Unauthenticated Remote Code Execution Palo Alto Networks customers can leverage a variety of product protections and updates to identify and defend against this threat. If you think you might have been compromised or have an urgent matter, get in touch with the [Unit 42 Incident Response team](https://start.paloaltonetworks.com/contact-unit42.html) or call: * North America: Toll Free: +1 (866) 486-4842 (866.4.UNIT42) * UK: +44.20.3743.3660 * Europe and Middle East: +31.20.299.3130 * Asia: +65.6983.8730 * Japan: +81.50.1790.0200 * Australia: +61.2.4062.7950 * India: 000 800 050 45107 * South Korea: +82.080.467.8774 ### Advanced WildFire The [Advanced WildFire](https://docs.paloaltonetworks.com/wildfire) machine-learning models and analysis techniques have been reviewed and updated in light of indicators associated with this activity. ### Next-Generation Firewalls With Advanced Threat Prevention [Next-Generation Firewall](https://docs.paloaltonetworks.com/wildfire) with the [Advanced Threat Prevention](https://docs.paloaltonetworks.com/wildfire) security subscription can help block attacks for this vulnerability by enabling Threat ID 510019 from Applications and Threats content version 9098. Decoder capabilities necessitate PAN-OS 11.1 or a later version for Threat ID support. ### Cloud-Delivered Security Services for the Next-Generation Firewall [Advanced URL Filtering](https://docs.paloaltonetworks.com/wildfire) and [Advanced DNS Security](https://docs.paloaltonetworks.com/wildfire) identify known URLs and domains associated with this activity as malicious. ### Cortex AgentiX Security analysts can use natural language to prompt the [Cortex AgentiX](https://www.paloaltonetworks.com/cortex/agentix) Threat Intel agent for a quick summary of sightings in their Cortex environment, to retrieve tenant-specific and global threat intelligence information for CVE-2026-0300. ### Cortex Xpanse Palo Alto Networks [Cortex Xpanse](https://docs.paloaltonetworks.com/wildfire) can identify exposed instances of the User-ID Authentication Portal potentially vulnerable to CVE-2026-0300. ## Indicators of Compromise * 67\.206.213\[.\]86 * 136\.0.8\[.\]48 * 146\.70.100\[.\]69 (C2 Staging) * 149\.104.66\[.\]84 * hxxp\[:\]//146.70.100\[.\]69:8000/php\_sess (EarthWorm Download) * hxxps\[:\]//github\[.\]com/Acebond/ReverseSocks5/releases/download/v2.2.0/ReverseSocks5-v2.2.0-linux-amd64.tar\[.\]gz (ReverseSocks5 Download) * e11f69b49b6f2e829454371c31ebf86893f82a042dae3f2faf63dcd84f97a584 (EarthWorm) * Safari/532.31 Mozilla/5.5 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/138.0.0.0 Safari/537.36 Edg/138.0.0.0 (Attacker User Agent String) * /var/tmp/linuxap, /var/tmp/linuxda, /var/tmp/linuxupdate (Tunneling Tools) * /tmp/.c (Unidentified Python Script) * /tmp/R5, /var/R5 (ReverseSocks5) *Updated May 8, 2026, at 9:20 a.m. PT, to update the product protections section, adding Cortex AgentiX and updating the Applications and Threats content version.* Back to top ### Tags * [CVE-2026-0300](https://unit42.paloaltonetworks.com/tag/cve-2026-0300/ "CVE-2026-0300") * [EarthWorm](https://unit42.paloaltonetworks.com/tag/earthworm/ "EarthWorm") * [PAN-OS](https://unit42.paloaltonetworks.com/tag/pan-os/ "PAN-OS") * [Remote Code Execution](https://unit42.paloaltonetworks.com/tag/remote-code-execution/ "Remote Code Execution") * [ReverseSocks5](https://unit42.paloaltonetworks.com/tag/reversesocks5/ "ReverseSocks5") * [Vulnerability](https://unit42.paloaltonetworks.com/tag/vulnerability/ "vulnerability") * [Zero-day](https://unit42.paloaltonetworks.com/tag/zero-day/ "zero-day") [Threat Research Center](https://unit42.paloaltonetworks.com "Threat Research") [Next: Copy Fail: What You Need to Know About the Most Severe Linux Threat in Years](https://unit42.paloaltonetworks.com/cve-2026-31431-copy-fail/ "Copy Fail: What You Need to Know About the Most Severe Linux Threat in Years") ### Table of Contents * ### Related Articles * [The Frontier AI Vulnerability Burst: Industrializing Autonomous Zero-Day Discovery in Open-Source Software](https://unit42.paloaltonetworks.com/frontier-ai-vulnerability-burst/ "article - table of contents") * [Pickle in the Middle -- Hijacking Vertex AI Model Uploads for Cross-Tenant RCE](https://unit42.paloaltonetworks.com/hijacking-vertex-ai-model/ "article - table of contents") * [Threat Brief: Active Exploitation of PAN-OS CVE-2026-0257](https://unit42.paloaltonetworks.com/active-exploitation-of-pan-os-cve-2026-0257/ "article - table of contents") ## Related Vulnerabilities Resources ![Pictorial representation of a group of people interacting with a dynamic 3D holographic display of colorful, undulating data waves on a table.](https://unit42.paloaltonetworks.com/wp-content/uploads/2025/09/11_Myth-Busting_Overview_1920x900-786x368.jpg) [![category icon](https://unit42.paloaltonetworks.com/wp-content/uploads/2025/08/Insights-icon-white.svg)Insights](https://unit42.paloaltonetworks.com/category/insights/) August 4, 2026 [#### The Frontier AI Vulnerability Burst: Industrializing Autonomous Zero-Day Discovery in Open-Source Software](https://unit42.paloaltonetworks.com/frontier-ai-vulnerability-burst/) * [AI](https://unit42.paloaltonetworks.com/tag/ai/ "AI") * [Frontier AI](https://unit42.paloaltonetworks.com/tag/frontier-ai/ "Frontier AI") * [Vulnerability Exploitation](https://unit42.paloaltonetworks.com/tag/vulnerability-exploitation/ "Vulnerability Exploitation") [Read now ![Right arrow](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-right-arrow-withtail.svg)](https://unit42.paloaltonetworks.com/frontier-ai-vulnerability-burst/ "The Frontier AI Vulnerability Burst: Industrializing Autonomous Zero-Day Discovery in Open-Source Software") ![Pictorial representation of AI-enabled autonomous cyberattacks. A digital illustration depicting abstract, interconnected data streams in vibrant colors on a dark blue background](https://unit42.paloaltonetworks.com/wp-content/uploads/2026/07/AdobeStock_992950050-3-782x440.jpeg) [![category icon](https://unit42.paloaltonetworks.com/wp-content/uploads/2024/06/icon-threat-research.svg)Threat Research](https://unit42.paloaltonetworks.com/category/threat-research/) July 30, 2026 [#### Chinese-Speaking Threat Actor Harnesses AI Models for Autonomous Cyberattacks](https://unit42.paloaltonetworks.com/autonomous-ai-cyber-attack-campaign/) * [ChatGPT](https://unit42.paloaltonetworks.com/tag/chatgpt/ "ChatGPT") * [Claude code](https://unit42.paloaltonetworks.com/tag/claude-code/ "Claude code") * [CVEs](https://unit42.paloaltonetworks.com/tag/cves/ "CVEs") [Read now ![Right arrow](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-right-arrow-withtail.svg)](https://unit42.paloaltonetworks.com/autonomous-ai-cyber-attack-campaign/ "Chinese-Speaking Threat Actor Harnesses AI Models for Autonomous Cyberattacks") ![Pictorial representation of three zero-day vulnerabilities in Siemens ROX II OT switches. Digital illustration of a global network featuring interconnected lines and nodes over a map of the world, highlighted with neon lights and digital elements.](https://unit42.paloaltonetworks.com/wp-content/uploads/2026/07/03_Vulnerabilities_1920x900-786x368.jpg) [![category icon](https://unit42.paloaltonetworks.com/wp-content/uploads/2024/06/icon-threat-research.svg)Threat Research](https://unit42.paloaltonetworks.com/category/threat-research/) July 17, 2026 [#### Three Steps to the Terminal: A Siemens ROX II Zero-Day Trilogy](https://unit42.paloaltonetworks.com/siemens-rox-ii-zero-day-vulnerabilities/) * [Command injection](https://unit42.paloaltonetworks.com/tag/command-injection/ "Command injection") * [CVE-2025-40947](https://unit42.paloaltonetworks.com/tag/cve-2025-40947/ "CVE-2025-40947") * [CVE-2025-40948](https://unit42.paloaltonetworks.com/tag/cve-2025-40948/ "CVE-2025-40948") [Read now ![Right arrow](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-right-arrow-withtail.svg)](https://unit42.paloaltonetworks.com/siemens-rox-ii-zero-day-vulnerabilities/ "Three Steps to the Terminal: A Siemens ROX II Zero-Day Trilogy") ![Pictorial representation of PAN-OS CVE-2026-0257. A vibrant city skyline at night, with tall skyscrapers and glowing digital beams extending into the sky, suggesting advanced technology and connectivity.](https://unit42.paloaltonetworks.com/wp-content/uploads/2026/06/07_Vulnerabilities_1920x900-786x368.jpg) [![category icon](https://unit42.paloaltonetworks.com/wp-content/uploads/2024/07/top-threats.svg)High Profile Threats](https://unit42.paloaltonetworks.com/category/top-cyberthreats/) June 9, 2026 [#### Threat Brief: Active Exploitation of PAN-OS CVE-2026-0257](https://unit42.paloaltonetworks.com/active-exploitation-of-pan-os-cve-2026-0257/) * [CVE-2026-0257](https://unit42.paloaltonetworks.com/tag/cve-2026-0257/ "CVE-2026-0257") * [Vulnerability](https://unit42.paloaltonetworks.com/tag/vulnerability/ "vulnerability") [Read now ![Right arrow](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-right-arrow-withtail.svg)](https://unit42.paloaltonetworks.com/active-exploitation-of-pan-os-cve-2026-0257/ "Threat Brief: Active Exploitation of PAN-OS CVE-2026-0257") ![Pictorial representation of a severe Linux vulnerability. Close-up of a woman wearing glasses and focusing intently on a computer screen.](https://unit42.paloaltonetworks.com/wp-content/uploads/2026/05/05_Vulnerabilities_1920x900-2-1-786x368.jpg) [![category icon](https://unit42.paloaltonetworks.com/wp-content/uploads/2024/07/top-threats.svg)High Profile Threats](https://unit42.paloaltonetworks.com/category/top-cyberthreats/) May 5, 2026 [#### Copy Fail: What You Need to Know About the Most Severe Linux Threat in Years](https://unit42.paloaltonetworks.com/cve-2026-31431-copy-fail/) * [Containers](https://unit42.paloaltonetworks.com/tag/containers/ "Containers") * [CVE-2026-31431](https://unit42.paloaltonetworks.com/tag/cve-2026-31431/ "CVE-2026-31431") * [Kubernetes](https://unit42.paloaltonetworks.com/tag/kubernetes/ "Kubernetes") [Read now ![Right arrow](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-right-arrow-withtail.svg)](https://unit42.paloaltonetworks.com/cve-2026-31431-copy-fail/ "Copy Fail: What You Need to Know About the Most Severe Linux Threat in Years") ![Pictorial representation of CVE-2023-33538. Abstract image of a glowing red Wi-Fi symbol on a circuit board, with intricate patterns and a futuristic appearance.](https://unit42.paloaltonetworks.com/wp-content/uploads/2026/04/04_Vulnerabilities_1920x900-786x368.jpg) [![category icon](https://unit42.paloaltonetworks.com/wp-content/uploads/2024/06/icon-threat-research.svg)Threat Research](https://unit42.paloaltonetworks.com/category/threat-research/) April 16, 2026 [#### A Deep Dive Into Attempted Exploitation of CVE-2023-33538](https://unit42.paloaltonetworks.com/exploitation-of-cve-2023-33538/) * [Botnet](https://unit42.paloaltonetworks.com/tag/botnet/ "botnet") * [Command injection](https://unit42.paloaltonetworks.com/tag/command-injection/ "Command injection") * [CVE-2023-33538](https://unit42.paloaltonetworks.com/tag/cve-2023-33538/ "CVE-2023-33538") [Read now ![Right arrow](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-right-arrow-withtail.svg)](https://unit42.paloaltonetworks.com/exploitation-of-cve-2023-33538/ "A Deep Dive Into Attempted Exploitation of CVE-2023-33538") ![Pictorial representation of BeyondTrust vulnerability CVE-2026-1731. Digital art depicting a stylized mountain range with vibrant blue and red hues. The peaks are accentuated by glowing particles and an abstract, starry backdrop, creating a futuristic landscape.](https://unit42.paloaltonetworks.com/wp-content/uploads/2026/02/14_Overview_1920x900-786x368.jpg) [![category icon](https://unit42.paloaltonetworks.com/wp-content/uploads/2024/07/top-threats.svg)High Profile Threats](https://unit42.paloaltonetworks.com/category/top-cyberthreats/) February 19, 2026 [#### VShell and SparkRAT Observed in Exploitation of BeyondTrust Critical Vulnerability (CVE-2026-1731)](https://unit42.paloaltonetworks.com/beyondtrust-cve-2026-1731/) * [Bash](https://unit42.paloaltonetworks.com/tag/bash/ "bash") * [CVE-2026-1731](https://unit42.paloaltonetworks.com/tag/cve-2026-1731/ "CVE-2026-1731") * [PowerShell](https://unit42.paloaltonetworks.com/tag/powershell/ "PowerShell") [Read now ![Right arrow](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-right-arrow-withtail.svg)](https://unit42.paloaltonetworks.com/beyondtrust-cve-2026-1731/ "VShell and SparkRAT Observed in Exploitation of BeyondTrust Critical Vulnerability (CVE-2026-1731)") ![](https://unit42.paloaltonetworks.com/wp-content/uploads/2026/02/AdobeStock_1020436911-786x440.jpeg) [![category icon](https://unit42.paloaltonetworks.com/wp-content/uploads/2024/07/top-threats.svg)High Profile Threats](https://unit42.paloaltonetworks.com/category/top-cyberthreats/) February 17, 2026 [#### Critical Vulnerabilities in Ivanti EPMM Exploited](https://unit42.paloaltonetworks.com/ivanti-cve-2026-1281-cve-2026-1340/) * [CVE-2026-1281](https://unit42.paloaltonetworks.com/tag/cve-2026-1281/ "CVE-2026-1281") * [CVE-2026-1340](https://unit42.paloaltonetworks.com/tag/cve-2026-1340/ "CVE-2026-1340") * [Ivanti](https://unit42.paloaltonetworks.com/tag/ivanti/ "Ivanti") [Read now ![Right arrow](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-right-arrow-withtail.svg)](https://unit42.paloaltonetworks.com/ivanti-cve-2026-1281-cve-2026-1340/ "Critical Vulnerabilities in Ivanti EPMM Exploited") ![Pictorial representation of CVE-2025-0921. Digital illustration of a map of North America with interconnected glowing lines and dots symbolizing network connections across the continent.](https://unit42.paloaltonetworks.com/wp-content/uploads/2026/01/06_Vulnerabilities_1920x900-2-1-786x368.jpg) [![category icon](https://unit42.paloaltonetworks.com/wp-content/uploads/2024/06/icon-threat-research.svg)Threat Research](https://unit42.paloaltonetworks.com/category/threat-research/) January 30, 2026 [#### Privileged File System Vulnerability Present in a SCADA System](https://unit42.paloaltonetworks.com/iconics-suite-cve-2025-0921/) * [CVE-2025-0921](https://unit42.paloaltonetworks.com/tag/cve-2025-0921/ "CVE-2025-0921") * [Privilege escalation](https://unit42.paloaltonetworks.com/tag/privilege-escalation/ "privilege escalation") * [SCADA](https://unit42.paloaltonetworks.com/tag/scada/ "SCADA") [Read now ![Right arrow](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-right-arrow-withtail.svg)](https://unit42.paloaltonetworks.com/iconics-suite-cve-2025-0921/ "Privileged File System Vulnerability Present in a SCADA System") * ![Slider arrow](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/slider-arrow-left.svg) * ![Slider arrow](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/slider-arrow-left.svg) ![Close button](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/close-modal.svg) ![Enlarged Image]() ![Newsletter](https://unit42.paloaltonetworks.com/wp-content/uploads/2026/03/unit42-footer-subscribe-desktop.png) ![UNIT 42 Small Logo](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/palo-alto-logo-small.svg) Get updates from Unit 42 ## Peace of mind comes from staying ahead of threats. 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