A use-after-free vulnerability in the Linux kernel's net/sched: cls_fw component can be exploited to achieve local privilege escalation.
When fw_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 76e42ae831991c828cffa8c37736ebfb831ad5ec.
CVE-2023-4207 - High Severity Vulnerability
Yocto Linux Embedded kernel
Library home page: https://git.yoctoproject.org/git/linux-yocto
Found in base branch: master
A use-after-free vulnerability in the Linux kernel's net/sched: cls_fw component can be exploited to achieve local privilege escalation. When fw_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 76e42ae831991c828cffa8c37736ebfb831ad5ec.
Publish Date: 2023-09-06
URL: CVE-2023-4207
Base Score Metrics: - Exploitability Metrics: - Attack Vector: Local - Attack Complexity: Low - Privileges Required: Low - User Interaction: None - Scope: Unchanged - Impact Metrics: - Confidentiality Impact: High - Integrity Impact: High - Availability Impact: High
For more information on CVSS3 Scores, click here.Type: Upgrade version
Origin: https://www.linuxkernelcves.com/cves/CVE-2023-4207
Release Date: 2023-09-06
Fix Resolution: v5.4.253,v5.10.190,v5.15.126,v6.1.45,v6.4.10,v6.5-rc5
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