Yüksek CVSS 7.8
CVE-2026-31700: Linux Kernel: yarış durumu
Açıklama (NVD)
In the Linux kernel, the following vulnerability has been resolved: net/packet: fix TOCTOU race on mmap'd vnet_hdr in tpacket_snd() In tpacket_snd(), when PACKET_VNET_HDR is enabled, vnet_hdr points directly into the mmap'd TX ring buffer shared with userspace. The kernel validates the header via __packet_snd_vnet_parse() but then re-reads all fields later in virtio_net_hdr_to_skb(). A concurrent userspace thread can modify the vnet_hdr fields between validation and use, bypassing all safety checks. The non-TPACKET path (packet_snd()) already correctly copies vnet_hdr to a stack-local variable. All other vnet_hdr consumers in the kernel (tun.c, tap.c, virtio_net.c) also use stack copies. The TPACKET TX path is the only caller of virtio_net_hdr_to_skb() that reads directly from user-controlled shared memory. Fix this by copying vnet_hdr from the mmap'd ring buffer to a stack-local variable before validation and use, consistent with the approach used in packet_snd() and all other callers.
Özet bilgiler
- Ürün
- Linux Linux Kernel
- CVSS v3.1
- 7.8
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS
- %0,11 (yüzdelik 1)
- CWE
- CWE-362
- Yama
- Mevcut
Etkilenen sürümler
| Ürün | Başlangıç | Bitiş | Düzeltildi |
|---|---|---|---|
| linux-linux-kernel | 4.6 | — | 6.6.136 |
| linux-linux-kernel | 6.7 | — | 6.12.84 |
| linux-linux-kernel | 6.13 | — | 6.18.25 |
| linux-linux-kernel | 6.19 | — | 7.0.2 |
| linux-linux-kernel | 7.1 | 7.1 | — |
| linux-linux-kernel | 7.1 | 7.1 | — |