CVE-2024-4436 is a vulnerability classified as uncontrolled resource consumption affecting the etcd package bundled with the Red Hat OpenStack platform. The root cause is an incomplete remediation of a prior vulnerability (CVE-2022-41723). Specifically, the etcd package uses the http2 implementation from golang.org/x/net/http2 rather than the updated and patched version provided by Red Hat Enterprise Linux (RHEL). This discrepancy means that the vulnerability fixed in RHEL's http2 package is not fully addressed in the OpenStack platform's etcd package. The vulnerability allows an unauthenticated remote attacker to trigger excessive resource consumption, potentially leading to denial of service (DoS) conditions. The CVSS v3.1 base score is 7.5, reflecting a high severity with network attack vector, low attack complexity, no privileges required, and no user interaction needed. The impact is limited to availability, with no confidentiality or integrity loss. No known exploits have been reported in the wild yet, but the vulnerability poses a risk to the stability and reliability of cloud services relying on etcd within Red Hat OpenStack environments. The fix requires updating the etcd package to use the correct, patched http2 library at compile time, ensuring the vulnerability is fully mitigated. Organizations should monitor for updates from Red Hat and apply patches promptly. This vulnerability underscores the risks associated with dependency management in complex open-source software stacks used in enterprise cloud platforms.

For European organizations, the impact of CVE-2024-4436 can be significant, especially for those deploying Red Hat OpenStack as part of their cloud infrastructure. Uncontrolled resource consumption can lead to denial of service, causing outages or degraded performance of critical cloud services and applications. This can affect service availability for end-users and internal operations, potentially disrupting business continuity. Given that no authentication or user interaction is required, attackers can remotely exploit this vulnerability, increasing the risk profile. Organizations in sectors such as finance, healthcare, telecommunications, and government, which rely heavily on cloud platforms for sensitive or critical workloads, may face operational and reputational damage if exploited. Additionally, the incomplete fix indicates potential supply chain weaknesses, which could undermine trust in vendor updates. The absence of known exploits currently provides a window for proactive mitigation, but the high severity score demands urgent attention to prevent future exploitation. Overall, the vulnerability threatens availability and operational stability of cloud environments in Europe.

1. Verify the version of the etcd package used within the Red Hat OpenStack platform to determine if it includes the vulnerable http2 implementation from golang.org/x/net/http2. 2. Apply patches or updates provided by Red Hat that recompile etcd with the correct, patched http2 package from Red Hat Enterprise Linux. 3. If patches are not yet available, consider rebuilding the etcd package manually with the updated http2 dependency to ensure the fix is applied. 4. Monitor resource usage metrics closely for unusual spikes in CPU, memory, or network usage that could indicate exploitation attempts. 5. Implement network-level protections such as rate limiting or filtering to reduce the risk of resource exhaustion attacks targeting etcd endpoints. 6. Restrict access to etcd services to trusted networks or authenticated users where possible to reduce exposure. 7. Maintain an inventory of all OpenStack deployments and their component versions to quickly identify affected systems. 8. Engage with Red Hat support and subscribe to security advisories to receive timely updates on patches and mitigation guidance. 9. Conduct regular security assessments and penetration tests focusing on cloud infrastructure components to detect potential exploitation vectors. 10. Educate DevOps and cloud operations teams about the importance of dependency management and supply chain security to prevent similar issues.