CVE-2026-64552
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.
Affected versions
Linux kernel versions
6.1.159,
6.6.117,
6.12.58,
6.17.8,
6.18
and later are affected. Fixed in
6.1.178,
6.6.145,
6.12.97,
6.18.40,
7.1.5,
7.2-rc1
and their respective stable series.
References
6 totalFrequently asked questions
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What is CVE-2026-64552?
CVE-2026-64552 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 6.1.159 onward and has been patched in 6.1.178, 6.6.145, 6.12.97 and others. CVE-2026-64552 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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Is there a patch available for CVE-2026-64552?
Yes. CVE-2026-64552 has been patched. Fixed versions include 6.1.178, 6.6.145, 6.12.97 and others. If you are running Linux kernel 6.1.159 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-64552 actively exploited?
No. CVE-2026-64552 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.