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Attackers rapidly weaponized React2Shell (CVE-2025-55182), a critical flaw in React Server Components and React/Next.js applications that enables unauthenticated remote code execution. Security reporting described the bug as one of the most consequential vulnerabilities of the year, with exploitation spreading across criminal and state-linked operations and defenders urged to prioritize emergency patching and monitoring. The flaw was also tied to broader shifts in the threat landscape, including more resilient malware campaigns, cloud-focused intrusions, and increasingly AI-enabled attack activity.
Large-scale exploitation followed disclosure, with more than 8.1 million attack sessions observed from over 8,000 unique source IPs spanning 101 countries, including substantial traffic routed through major cloud providers such as AWS. Researchers also linked the vulnerability to follow-on malware activity, including the EtherRAT campaign, which used Ethereum smart contracts for command-and-control, while reporting highlighted advanced evasion methods such as AMSI bypass and rapid IP rotation that reduced the effectiveness of static defenses. The volume and sophistication of the attacks underscored the need for behavioral detection, dynamic threat intelligence, and immediate remediation of exposed internet-facing systems.
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5 events from the most recent confirmed update back to the earliest known activity.
Cyber Security News reported that attackers had launched more than 8.1 million attack sessions against React2Shell since its disclosure. The activity used over 8,000 unique source IPs across 101 countries, with substantial traffic originating from major cloud providers and employing rapid IP rotation and AMSI-bypass techniques.
Sysdig reported a DDoS attack that disrupted French postal and banking services. The incident was cited among notable cybersecurity events observed in December 2025.
Sysdig reported that the European Space Agency suffered a breach involving significant data theft. According to the report, network segmentation limited the overall impact of the incident.
Sysdig's Threat Research Team identified EtherRAT, a sophisticated multi-stage malware campaign that used Ethereum smart contracts for command-and-control and exploited React2Shell. The campaign was highlighted as part of the December 2025 threat landscape.
PolySwarm described React2Shell (CVE-2025-55182) as the most impactful vulnerability of 2025, saying the flaw in React/Next.js applications enabled unauthenticated remote code execution and was rapidly weaponized by both state-sponsored and criminal actors. Separate reporting also described active exploitation of the flaw in December 2025.
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Threat actors are actively exploiting **React2Shell**, a critical remote code execution flaw in React Server Components tracked as `CVE-2025-55182`, with related exposure also noted in Next.js as `CVE-2025-66478`. The bug stems from insecure deserialization in the React Server Components Flight protocol and allows unauthenticated attackers to upload malicious payloads and execute arbitrary code on vulnerable internet-facing servers. Public disclosure was quickly followed by advisories, proof-of-concept code, and reports of broad exploitation, while Microsoft and other researchers said hundreds of machines had already been hacked. Follow-on campaigns have been widespread and largely opportunistic, ranging from credential-harvesting operations to malware deployment against organizations in multiple sectors and regions. Cisco Talos-linked reporting said at least **766 servers** were compromised by an automated campaign that stole SSH keys, cloud tokens, API keys, Kubernetes and GitHub credentials, Docker metadata, and other environment secrets, including keys tied to AI platforms and payment services. Other investigations tied exploitation to **XMRig**, **RustoBot**, **Kaiji**, **Sliver**, **CrossC2**, **Tactical RMM**, **VShell**, and **EtherRAT**, along with persistence, reconnaissance, DNS-based exfiltration, and SSH key installation, underscoring how rapidly the vulnerability was weaponized after disclosure.
Jun 29, 2026
A severe remote code execution vulnerability tracked as **`CVE-2025-55182`** was disclosed in **React Server Components** and quickly became known as **React2Shell**, with reporting indicating that exploitation spread soon after public disclosure. Security coverage from eSentire, BitSight, and Computer Weekly described the flaw as affecting React and Next.js environments, warned defenders to assess internet-exposed applications, and noted that attackers were moving from proof-of-concept activity toward broader exploitation. Public GitHub repositories rapidly appeared with exploit code, scanners, and remediation-focused projects, including tools explicitly labeled for **`CVE-2025-55182`** and **React2Shell** detection or exploitation. Repositories such as **`React2Shell-PoC`**, multiple **PoC scanners**, auto-exploit projects, and checkers lowered the barrier to weaponization, while at least one repository advertised fixes for React 19 users. The volume and speed of public tooling indicate that organizations running React Server Components or Next.js services faced immediate pressure to identify exposed systems, apply vendor fixes, and monitor for signs of remote code execution attempts.
Jul 12, 2026
A critical remote code execution vulnerability, dubbed **React2Shell**, was discovered in the React 19 library, specifically affecting React Server Components. The flaw allows unauthenticated attackers to execute arbitrary code on servers by sending crafted requests, making it a severe risk for organizations using default React and Next.js deployments. Within hours of public disclosure, security firms including Google’s Threat Intelligence Group and AWS confirmed active exploitation in the wild, highlighting the shrinking window between vulnerability awareness and real-world attacks. Researchers from Wiz and Unit 42 demonstrated that even clean, default deployments were susceptible, emphasizing the widespread impact due to the popularity of these frameworks. Threat actors rapidly weaponized the React2Shell vulnerability, with the RondoDoX botnet launching automated exploitation campaigns targeting both web applications and IoT devices. CloudSEK’s analysis of command and control logs revealed a multi-month campaign, with a significant spike in attacks following the vulnerability’s disclosure in December 2025. The RondoDoX botnet deployed various payloads, including web shells and cryptominers, and quickly adapted its infrastructure in response to security firm reports. Organizations with technology stacks overlapping the targeted vectors were promptly alerted, underscoring the urgent need for patching and monitoring in environments using React 19 and Next.js.
Jun 29, 2026