CVE-2025-9784 identifies a vulnerability in the Undertow web server component used within the Red Hat build of Apache Camel for Spring Boot 4. The flaw arises from the server's failure to properly limit or throttle resource allocation when handling malformed client requests that cause server-side stream resets. Specifically, attackers can send crafted requests that repeatedly trigger stream aborts on the server without incrementing abuse counters designed to detect such behavior. This leads to excessive consumption of server resources, resulting in degraded performance or denial of service (DoS). The vulnerability is categorized under CWE-404 (Improper Resource Shutdown or Release), highlighting a weakness in resource management rather than a protocol-level defect. The CVSS 3.1 base score of 7.5 reflects high severity due to the vulnerability's network attack vector (AV:N), low attack complexity (AC:L), no privileges required (PR:N), no user interaction (UI:N), and impact limited to availability (A:H) without affecting confidentiality or integrity. No known exploits are currently reported in the wild, but the potential for disruption is significant, especially in environments where Undertow handles critical web traffic. The vulnerability underscores the importance of robust resource management and abuse detection mechanisms in server implementations to prevent denial of service through resource exhaustion.

For European organizations, the primary impact of CVE-2025-9784 is the risk of denial of service attacks that can disrupt availability of web services relying on the affected Red Hat build of Apache Camel for Spring Boot 4. This can lead to downtime, degraded user experience, and potential loss of business continuity, especially for enterprises and public sector entities providing critical online services. The vulnerability does not compromise confidentiality or integrity but can severely impact operational stability. Organizations in sectors such as finance, healthcare, government, and telecommunications that deploy Undertow-based applications are particularly vulnerable. The ease of exploitation—requiring no authentication or user interaction—means attackers can launch attacks remotely at scale. This could also increase the risk of cascading failures in interconnected systems or cloud environments hosting these applications. Additionally, the lack of current patches or known exploits means organizations must proactively implement mitigations to reduce exposure until official fixes are available.

1. Implement strict rate limiting and throttling on incoming requests to detect and block excessive stream reset attempts before they exhaust server resources. 2. Monitor server logs and metrics for abnormal patterns of stream aborts or resets that could indicate exploitation attempts. 3. Deploy Web Application Firewalls (WAFs) or Intrusion Prevention Systems (IPS) configured to detect and mitigate malformed request patterns targeting Undertow. 4. Isolate critical services using Undertow behind load balancers or reverse proxies that can absorb or filter malicious traffic. 5. Engage with Red Hat and Apache Camel communities to track patch releases and apply updates promptly once available. 6. Conduct regular security assessments and penetration tests focusing on resource exhaustion vectors. 7. Consider architectural changes to reduce reliance on vulnerable components or introduce redundancy to maintain availability during attacks. 8. Educate development and operations teams about this specific vulnerability to ensure awareness and rapid response capabilities.