# CVE-2026-98018: net: mctp: i3c: serialize probe with bus removal

CVE-2026-98018 is fixed in 2 products on 1 platform, first by DEBIAN-CVE-2026-98018, released September 29, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-98018
- Priority: Routine
- CVSS: n/a
- EPSS: 0.0017
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 25, 2026
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-98018

## Description

In the Linux kernel, the following vulnerability has been resolved:  net: mctp: i3c: serialize probe with bus removal  mctp_i3c_probe() drops busdevs_lock after finding the matching bus. A concurrent I3C_NOTIFY_BUS_REMOVE can then unregister and free the bus netdev before probe passes its private data to mctp_i3c_add_device(). The latter consequently adds a list node through a freed mbus pointer.  Keep busdevs_lock held until the device has been added. This also satisfies the __must_hold annotation on mctp_i3c_add_device().

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 13.5 (trixie) | 6.12.111-1 | [DEBIAN-CVE-2026-98018](https://patchblox.com/security/data/fix/linux/debian-cve-2026-98018.md) | Sep 29, 2026 |
| Linux | linux Debian 14 | 7.2.7-1 | [DEBIAN-CVE-2026-98018](https://patchblox.com/security/data/fix/linux/debian-cve-2026-98018.md) | Sep 29, 2026 |
| Linux | linux-6.12 Debian 12.15 (bookworm) | 6.12.111-1~deb12u1 | [DEBIAN-CVE-2026-98018](https://patchblox.com/security/data/fix/linux/debian-cve-2026-98018.md) | Sep 29, 2026 |

---

Data as of 2026-11-08T13:06:02Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data

Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.