CVE-2024-3567 is a 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 flaw 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. SCTP is a transport-layer protocol used in some network communications, and QEMU’s emulation of network hardware processes such packets. The assertion failure indicates that an unexpected condition is met during checksum calculation, causing QEMU to terminate abruptly. This can be exploited by a malicious guest virtual machine that crafts specially fragmented SCTP packets to trigger the assertion and crash the QEMU process hosting it. The impact is a denial of service on the host side, potentially affecting availability of the virtualized environment. The vulnerability requires local privileges within the guest VM (AV:L - adjacent/local), low attack complexity (AC:L), and privileges (PR:L), but no user interaction (UI:N). The scope is unchanged (S:U), and there is no impact on confidentiality or integrity, only availability (A:H). No known public exploits have been reported yet. This vulnerability is particularly relevant for environments that use QEMU for virtualization, including cloud providers, hosting services, and enterprises running virtualized workloads on QEMU/KVM. Since QEMU is widely used in open-source virtualization stacks, the vulnerability could affect a broad range of deployments if unpatched.

For European organizations, the primary impact of CVE-2024-3567 is the potential for denial of service on virtualized infrastructure running QEMU 8.2.92. This can disrupt critical services hosted on virtual machines, leading to downtime and operational interruptions. Organizations relying on QEMU-based virtualization for cloud services, private data centers, or edge computing could experience service outages if a malicious guest exploits this vulnerability. While the vulnerability does not compromise data confidentiality or integrity, the availability impact could affect business continuity, especially for sectors requiring high uptime such as finance, telecommunications, and public services. Additionally, the need for local guest privileges means that insider threats or compromised guest VMs pose a risk. The absence of known exploits reduces immediate risk, but the medium severity rating and ease of triggering a crash warrant proactive mitigation. European cloud providers and enterprises using QEMU should assess their exposure and prioritize remediation to avoid service disruptions.

To mitigate CVE-2024-3567, European organizations should first apply any available patches or updates from QEMU maintainers or their Linux distribution vendors as soon as they are released. In the absence of patches, organizations can implement the following specific measures: 1) Restrict and monitor guest VM network traffic to detect and block malformed SCTP packets that could trigger the assertion failure. 2) Limit guest VM privileges to minimize the ability of attackers to craft malicious packets. 3) Employ network segmentation and isolation to reduce the risk of compromised guests affecting critical infrastructure. 4) Use virtualization security tools that monitor QEMU process stability and automatically restart or isolate affected VMs upon crashes. 5) Regularly audit and update virtualization software stacks to avoid running vulnerable versions. 6) Consider disabling SCTP support in QEMU if it is not required by workloads, reducing the attack surface. These targeted actions, combined with standard security hygiene, will help reduce the risk of denial of service caused by this vulnerability.