# CVE-2025-39872: linux: In the Linux kernel, the following vulnerability has been resolved:  hsr: hold rcu and dev lock for hsr_get_port_ndev...

CVE-2025-39872 is fixed in linux on 1 platform, first by DEBIAN-CVE-2025-39872, released September 23, 2025. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2025-39872
- Priority: Routine
- CVSS: 5.5 (medium)
- EPSS: 0.0016
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 23, 2025

## Description

In the Linux kernel, the following vulnerability has been resolved:  hsr: hold rcu and dev lock for hsr_get_port_ndev  hsr_get_port_ndev calls hsr_for_each_port, which need to hold rcu lock. On the other hand, before return the port device, we need to hold the device reference to avoid UaF in the caller function.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 13.5 (trixie) | 6.12.69-1 | [DEBIAN-CVE-2025-39872](https://patchblox.com/security/data/fix/linux/debian-cve-2025-39872.md) | Sep 23, 2025 |
| Linux | linux Debian 14 | 6.16.8-1 | [DEBIAN-CVE-2025-39872](https://patchblox.com/security/data/fix/linux/debian-cve-2025-39872.md) | Sep 23, 2025 |

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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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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