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CVE-2023-4206 (GCVE-0-2023-4206)

Vulnerability from cvelistv5 – Published: 2023-09-06 13:53 – Updated: 2025-02-13 17:09
VLAI
Title
Use-after-free in Linux kernel's net/sched: cls_route component
Summary
A use-after-free vulnerability in the Linux kernel's net/sched: cls_route component can be exploited to achieve local privilege escalation. When route4_change() is called on an existing filter, the whole tcf_result struct is always copied into the new instance of the filter. This causes a problem when updating a filter bound to a class, as tcf_unbind_filter() is always called on the old instance in the success path, decreasing filter_cnt of the still referenced class and allowing it to be deleted, leading to a use-after-free. We recommend upgrading past commit b80b829e9e2c1b3f7aae34855e04d8f6ecaf13c8.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Kernel Affected: 3.18 , < 6.5 (custom)
guessed Create a notification for this product.
Date Public
2023-08-01 03:10
Credits
valis Bing-Jhong Billy Jheng
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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