CVE-2025-39827

Published Sep 16, 2025

Last updated a month ago

CVSS medium 5.5

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: net: rose: include node references in rose_neigh refcount Current implementation maintains two separate reference counting mechanisms: the 'count' field in struct rose_neigh tracks references from rose_node structures, while the 'use' field (now refcount_t) tracks references from rose_sock. This patch merges these two reference counting systems using 'use' field for proper reference management. Specifically, this patch adds incrementing and decrementing of rose_neigh->use when rose_neigh->count is incremented or decremented. This patch also modifies rose_rt_free(), rose_rt_device_down() and rose_clear_route() to properly release references to rose_neigh objects before freeing a rose_node through rose_remove_node(). These changes ensure rose_neigh structures are properly freed only when all references, including those from rose_node structures, are released. As a result, this resolves a slab-use-after-free issue reported by Syzbot.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Modified
Products
linux_kernel, debian_linux

Risk scores

CVSS 3.1

Type
Primary
Base score
5.5
Impact score
3.6
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

Weaknesses

nvd@nist.gov
NVD-CWE-Other

Social media

Hype score
Not currently trending

  1. CVE-2025-39827 In the Linux kernel, the following vulnerability has been resolved: net https://t.co/scEoijOWV3

    @VulmonFeeds

    16 Sept 2025

    28 Impressions

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  2. CVE-2025-39827 In the Linux kernel, the following vulnerability has been resolved: net: rose: include node references in rose_neigh refcount Current implementation maintains two s… https://t.co/t8z3w6937E

    @CVEnew

    16 Sept 2025

    108 Impressions

    0 Retweets

    0 Likes

    0 Bookmarks

    1 Reply

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Configurations

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References

Sources include official advisories and independent security research.