{"id":"AZL-94029","summary":"CVE-2026-64552 affecting package kernel for versions less than 6.6.145.2-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nvirtio-net: fix len check in receive_big()\n\nreceive_big() bounds the device-announced length by\n(big_packets_num_skbfrags + 1) * PAGE_SIZE.  That is still too loose:\nadd_recvbuf_big() sets sg[1] to start at offset\nsizeof(struct padded_vnet_hdr) into the first page, so the chain\nactually carries hdr_len + (PAGE_SIZE - sizeof(padded_vnet_hdr)) +\nbig_packets_num_skbfrags * PAGE_SIZE bytes -- 20 bytes less than the\ncheck allows for the common hdr_len == 12 case.\n\nA malicious virtio backend can announce a len in that gap.  page_to_skb()\nthen walks one frag past the page chain, storing a NULL page-\u003eprivate\ninto skb_shinfo()-\u003efrags[MAX_SKB_FRAGS], which is both an out-of-bounds\nwrite past the static frag array and a NULL frag handed up the rx path.\n\nBound len by the size add_recvbuf_big() actually advertised.","modified":"2026-08-28T17:47:36.574987525Z","published":"2026-07-27T21:17:08Z","upstream":["CVE-2026-64552"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64552"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.6.145.2-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-94029.json"}}],"schema_version":"1.9.0"}