CVE-2024-3567 is a medium-severity vulnerability identified in QEMU version 8.2.92, specifically within the update_sctp_checksum() function located in the hw/net/net_tx_pkt.c source file. The vulnerability arises due to an assertion failure triggered when QEMU attempts to calculate the checksum of a short-sized fragmented SCTP (Stream Control Transmission Protocol) packet. This assertion failure is reachable by a malicious guest virtual machine, which can exploit this flaw to cause QEMU to crash, resulting in a denial of service (DoS) condition. The vulnerability does not impact confidentiality or integrity but affects availability by crashing the host process running the QEMU hypervisor. The CVSS 3.1 base score is 5.5, reflecting a medium severity level. The attack vector is local (AV:L), requiring low attack complexity (AC:L) and low privileges (PR:L) on the guest VM, with no user interaction (UI:N) needed. The scope remains unchanged (S:U), and the impact is limited to availability (A:H), with no impact on confidentiality or integrity. There are no known exploits in the wild at the time of publication, and no patches or mitigations are explicitly linked in the provided data, though it is expected that QEMU maintainers will release updates. This vulnerability primarily affects environments where QEMU is used as a hypervisor or virtual machine monitor, especially those that allow untrusted or semi-trusted guests to run SCTP traffic that could trigger the checksum calculation path. The flaw is a denial of service vector rather than a code execution or privilege escalation vulnerability, but it can disrupt services relying on QEMU virtualization.

For European organizations, the impact of CVE-2024-3567 centers on availability disruptions in virtualized environments using QEMU 8.2.92. Organizations relying on QEMU for critical infrastructure, cloud services, or network function virtualization could experience service outages if a malicious or compromised guest VM triggers this assertion failure. This is particularly relevant for data centers, cloud providers, telecom operators, and enterprises using QEMU-based virtualization stacks. The denial of service could lead to downtime, impacting business continuity and potentially causing cascading effects if QEMU hosts multiple critical workloads. However, since exploitation requires local guest VM access with low privileges and no user interaction, the threat is mostly limited to environments where untrusted or less-trusted guests are permitted. Confidentiality and integrity of data remain unaffected, but availability degradation could affect service level agreements and operational reliability. The absence of known exploits reduces immediate risk, but proactive mitigation is advised to prevent potential future abuse.

1. Upgrade QEMU to a version where this vulnerability is patched once an official fix is released by QEMU maintainers or your Linux distribution vendor. 2. Restrict guest VM privileges and network capabilities to minimize the ability of guests to send malformed SCTP packets. 3. Implement strict network segmentation and filtering to control SCTP traffic between guests and from guests to the host. 4. Monitor QEMU logs and host system stability to detect abnormal crashes or assertion failures indicative of exploitation attempts. 5. Use security-hardened configurations for QEMU and the host OS, including limiting access to the hypervisor management interfaces. 6. Consider deploying intrusion detection or anomaly detection systems that can identify unusual SCTP packet patterns or guest behavior. 7. If possible, disable SCTP support in QEMU if it is not required by your workloads to reduce the attack surface. 8. Regularly review and apply security advisories from QEMU and Linux distributions to stay current with patches and mitigations.