CVE-2025-12464 is a stack-based buffer overflow vulnerability located in the QEMU e1000 network device driver, specifically within the e1000_receive_iov() function. The root cause stems from a recent code refactor where padding for short network frames was centralized into the net core code, but the e1000 device's receive code still processes short frames in loopback mode. This discrepancy allows a malicious guest operating within a virtual machine to send specially crafted short frames that trigger a buffer overrun on the host's QEMU process. The overflow can cause the QEMU process to crash, resulting in a denial of service on the host system. The vulnerability does not allow privilege escalation or data leakage but impacts availability. Exploitation requires local access to the guest VM but no special privileges or user interaction. The affected product is Red Hat Enterprise Linux 10, version 8.1.0, which bundles QEMU with the vulnerable e1000 device implementation. The CVSS 3.1 vector (AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) reflects that the attack vector is local (guest VM), with low attack complexity, no privileges required, no user interaction, unchanged scope, no confidentiality or integrity impact, but high impact on availability. No known exploits are currently reported in the wild. The vulnerability was published on October 31, 2025, and is assigned a medium severity rating. The issue highlights the risks of virtual device code refactoring without fully accounting for all code paths, especially in loopback or edge-case scenarios. Organizations using QEMU with the e1000 device on affected Red Hat Enterprise Linux versions should monitor for patches and consider temporary mitigations such as disabling loopback mode or restricting guest network capabilities.

For European organizations, the primary impact of CVE-2025-12464 is a denial of service condition on hosts running QEMU with the e1000 network device, particularly within Red Hat Enterprise Linux 10 environments. This can disrupt critical virtualized infrastructure, affecting availability of services hosted on virtual machines. While confidentiality and integrity are not directly impacted, the loss of availability could affect business continuity, especially in sectors relying heavily on virtualization such as finance, telecommunications, and government services. Organizations using cloud or private data centers with Red Hat Enterprise Linux 10 and QEMU virtualization are at risk if guest users can be malicious or compromised. The vulnerability could be exploited by insider threats or attackers who gain guest VM access, potentially leading to host instability or crashes. This may also impact compliance with European regulations requiring high availability and operational resilience. The lack of known exploits reduces immediate risk, but the medium severity and ease of exploitation from a guest VM warrant proactive mitigation to avoid service disruptions.

1. Apply official patches from Red Hat as soon as they become available to address the buffer overflow in the QEMU e1000 device. 2. Until patches are deployed, consider disabling or restricting the use of the e1000 network device in QEMU virtual machines, or switch to alternative virtual network devices that are not vulnerable. 3. Limit guest VM capabilities by enforcing strict network policies and isolating untrusted guests to reduce the risk of malicious frame injection. 4. Disable loopback mode in the virtual network device if feasible, as the vulnerability is triggered via loopback frame processing. 5. Monitor QEMU host processes for crashes or unusual behavior indicative of exploitation attempts. 6. Implement host-level resource limits and watchdogs to automatically recover from QEMU process failures. 7. Conduct regular security audits of virtualized environments to detect unauthorized guest activity. 8. Educate system administrators and security teams about this specific vulnerability and its exploitation vector to improve detection and response readiness.