CVE Catalog

CVE-2026-64552

HighCVSS 8.4
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.14%

4th percentile - higher than 4% of all known CVEs

Summary

In the Linux kernel, the virtio-net driver's receive_big() function checks the device-announced length too loosely, allowing a malicious virtio backend to write out-of-bounds past the frag array in skb. This can lead to NULL pointer write and potential exploitation.

Risk Assessment

Organizations using virtio network interfaces may be vulnerable to attacks from a malicious backend, potentially causing system crashes or code execution.

Recommendation

Apply the Linux kernel patch that bounds the length check to the actual size advertised by add_recvbuf_big().

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: virtio-net: fix len check in receive_big() receive_big() bounds the device-announced length by (big_packets_num_skbfrags + 1) * PAGE_SIZE. That is still too loose: add_recvbuf_big() sets sg[1] to start at offset sizeof(struct padded_vnet_hdr) into the first page, so the chain actually carries hdr_len + (PAGE_SIZE - sizeof(padded_vnet_hdr)) + big_packets_num_skbfrags * PAGE_SIZE bytes -- 20 bytes less than the check allows for the common hdr_len == 12 case. A malicious virtio backend can announce a len in that gap. page_to_skb() then walks one frag past the page chain, storing a NULL page->private into skb_shinfo()->frags[MAX_SKB_FRAGS], which is both an out-of-bounds write past the static frag array and a NULL frag handed up the rx path. Bound len by the size add_recvbuf_big() actually advertised.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS