---
cve: "CVE-2026-64552"
severity: "HIGH"
cvss: 8.4
epss: "14%"
vendor: "Linux"
kev: false
exploited: false
published: "2026-07-27 20:10:40"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-15T06:11:34+02:00"
---

# CVE-2026-64552

> 8.4 HIGH

## Beschreibung

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.

## CVSS-Vektor

```
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Lokal | good |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |
| S Scope | Unverändert | good |
| C Vertraulichkeit | Hoch | bad |
| I Integrität | Hoch | bad |
| A Verfügbarkeit | Hoch | bad |

## Patch verfügbar (OSV)

- Kernel ≥ 6.1.178
- Kernel ≥ 6.6.145
- Kernel ≥ 6.12.97
- Kernel ≥ 6.18.40
- Kernel ≥ 7.1.5

## Referenzen

- <https://git.kernel.org/stable/c/f9451d0fd5ba635dcabb49bfe456a6db734a8986>
- <https://git.kernel.org/stable/c/38e94d63e29f4a5c6eae87ee2c02101aaa321502>
- <https://git.kernel.org/stable/c/fbeb65154583879d556ea94cb2f15888e9470f3d>
- <https://git.kernel.org/stable/c/c7fc9adf4e006155f7f2aeda052fbcde25cdcc49>
- <https://git.kernel.org/stable/c/e6b8463b7d791f3886d7584259d6e9f06a69f12e>
- <https://git.kernel.org/stable/c/9e5ad06ea826322ce8c58b4a68442a96f600c3c4>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-64552) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_