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.
:heavy_check_mark: This issue was automatically closed by Mend because the vulnerable library in the specific branch(es) was either marked as ignored or it is no longer part of the Mend inventory.
CVE-2023-4207 - High Severity Vulnerability
Vulnerable Library - linux-yoctov5.4.51
Yocto Linux Embedded kernel
Library home page: https://git.yoctoproject.org/git/linux-yocto
Found in HEAD commit: f1b7c617b9b8f4135ab2f75a0c407cc44d43683f
Found in base branch: master
Vulnerable Source Files (2)
/net/sched/cls_fw.c /net/sched/cls_fw.c
Vulnerability Details
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
CVSS 3 Score Details (7.8)
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.Suggested Fix
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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