CVE-2026-97990

A flaw was found in the Linux kernel's vHost Data Path Acceleration (vDPA) network simulator driver. When a packet transmission pull operation fails, a negative error code is improperly treated as an unsigned value, resulting in an excessively large buffer length during receive processing. A local user could exploit this flaw to cause out-of-bounds memory access, leading to a kernel crash and Denial of Service (DoS).

A signed error result from vringh_iov_pull_iotlb can be used as an unsigned length in the vdpa_sim_net TX to RX path. A negative pull result can therefore become a very large size_t value and can cause receive_filter and vringh_iov_push_iotlb to read beyond the PAGE_SIZE net buffer. This may crash the host kernel and may copy unintended host memory into a guest controlled RX buffer. For the CVSS the PR:L is used because reliable triggering requires a local user or guest context that can control a vDPA virtqueue or an assigned virtual device. The issue is not directly network reachable from an external network client. Impact is at least local denial of service and may include host memory disclosure to a guest or local tenant.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.