CISA Flags Actively Exploited Ray Flaw That Can Trigger Browser-Based RCE

Summary

CISA has added a critical vulnerability in the Ray framework, CVE-2025-62593, to its Known Exploited Vulnerabilities catalog due to active exploitation. This flaw allows for browser-based remote code execution via DNS rebinding attacks, primarily impacting developers in development/testing environments. The vulnerability has been exploited by the RondoDox botnet and in a campaign to mine cryptocurrency using compromised GPUs.

Full text

CISA Flags Actively Exploited Ray Flaw That Can Trigger Browser-Based RCE Ravie LakshmananAug 18, 2026Vulnerability / Network Security The U.S. Cybersecurity and Infrastructure Security Agency (CISA) on Monday added a critical flaw impacting Ray to its Known Exploited Vulnerabilities (KEV) catalog, citing evidence of active exploitation. Ray is an open-source, Python-native distributed computing framework designed to scale artificial intelligence and machine learning workloads. As of writing, the GitHub project has more than 43,500 stars and has been forked over 7,900 times. The vulnerability in question relates to CVE-2025-62593 (CVSS score: 9.4), which can result in remote code execution via web browsers like Mozilla Firefox and Apple Safari by means of a DNS rebinding attack. "Due to the longstanding decision by the Ray Development team to not implement any sort of authentication on critical endpoints, like the /api/jobs & /api/job_agent/jobs/ has once again led to a severe vulnerability that allows attackers to execute arbitrary code against Ray," according to an advisory shared by Ray maintainers in November 2025. "This time in a development context via the browsers Firefox and Safari." The issue, at its core, stems from insufficient controls against browser-based attacks, specifically scenarios where the User-Agent header can be modified. "Combined with a DNS rebinding attack against the browser, and this vulnerability is exploitable against a developer running Ray who inadvertently visits a malicious website, or is served a malicious advertisement," the project maintainers added. It's worth noting that the defect primarily impacts developers running development/testing environments with Ray. Should a targeted victim fall prey to a phishing attack, or be served a malicious ad, it can lead to the execution of arbitrary shell code on their machine. The project maintainers also noted that the attack can also be extended to attack network-adjacent instances of Ray by leveraging the browser as a confused deputy intermediary to target Ray instances running inside a private corporate network. The issue has been addressed in version 2.52.0 of the Python package. Ray has credited Oligo security researcher Avi Lumelsky with discovering the fetch bypass and Jonathan Leitschuh for coming up with the DNS rebinding attack. CISA has not shared any details of how the vulnerability is being exploited in the wild. However, a BitSight report from March 2026 revealed that the threat actors behind the RondoDox DDoS botnet had incorporated the vulnerability into their arsenal two days before it was publicly disclosed on November 26, 2025, because of the availability of a proof-of-concept (PoC) exploit. According to Oligo, unpatched Ray instances have also been at the receiving end of cyber attacks that aim to turn infected clusters with NVIDIA GPUs into a self-replicating cryptocurrency mining botnet as part of a campaign dubbed ShadowRay 2.0. In light of active exploitation of CVE-2025-62593, Federal Civilian Executive Branch (FCEB) agencies are recommended to apply necessary fixes and mitigations by August 20, 2026. Found this article interesting? Follow us on Google News, Twitter and LinkedIn to read more exclusive content we post. SHARE     Tweet Share Share Share SHARE  AI Security, botnet, cryptocurrency, Cyber Attack, ddos, network security, Open Source, remote code execution, Threat Intelligence, Vulnerability ⚡ Top Stories This Week Azure Cosmos DB Flaw Exposed Platform-Wide Key That Could Access Any Database Anthropic Says Claude Mistook the Open Internet for a CTF and Breached Three Organizations Researchers Report 84 Flaws in 4G and 5G Cores, Including a Session Hijacking Flaw Cheap Android TV Boxes Pose as Phones and Turn Owners’ Broadband Into Proxies N-able Says Attackers Take Over N-central Servers After Initial Fix Proves Incomplete Google Password Manager Attacks Could Let Malware Hijack Passkey-Protected Accounts New cPanel Critical Flaw Could Let Hosting Customers Run SQL as Database Root Keyv-Linked npm Worm Poisons Hundreds of Packages, Plants Claude Code and VS Code Hooks Claude Mythos 5 Tried to Backdoor a Real Open-Source Project in Testing, Then Vouched for Itself Critical Gitea Flaw Let Unauthenticated Attackers Read Server Files via Org-Mode Markup Poison Claude Sells Discounted Claude Access While Its Operator Sees Every Customer Prompt Over 250 ClickFix Domains Use Browser Fingerprinting to Hide macOS Malware Lures Chinese-Made Zbtlink Routers Ship With Backdoor That Opens Unauthenticated Root Shells Apple iCloud Private Relay Can Expose Real IPs Through WebKit Proxy Bypasses ThreatsDay: Odysseus RCE, Samsung One-Click Takeover, iCloud Backdoor Fight + 27 More Stories New Interrupt Injection Attack Can Bypass Spectre v2 Defenses on Intel and AMD CPUs New Zapscape KVM Flaw Could Let Privileged L1 Guest Code Escape to Linux Hosts New NatJack Attacks Hijack TCP Sessions and Spoof DNS by Manipulating NAT Tables 18-Year-Old Linux SCTP Flaw Could Let Local Users Gain Root and Escape Containers New WordPress Pre-Auth XSS Could Lead to PHP Code Execution - Patch ASAP Metabase Zero-Day Exploited in Wild Allows Admin Access Without Authentication Atlassian Rovo Can Be Tricked Into Sending Jira and Confluence Data to Attackers ⭐ Featured Resources See How to Stop the Browser-Based Attacks Your Existing Stack Misses [Book a Live Demo] [Webinar] See Where Claude Fits in the SOC and Where It Falls Short at Scale Defend Against One-Click AI Memory Poisoning — Download the Cheat Sheet Benchmark Your Defenses Against 338M+ Attack Simulations — Download the Blue Report 2026

Indicators of Compromise

• cve — CVE-2025-62593

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