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.
History

Thu, 13 Feb 2025 17:15:00 +0000

Type Values Removed Values Added
Description 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. 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-icon MITRE

Status: PUBLISHED

Assigner: Google

Published:

Updated: 2025-02-13T17:09:17.204Z

Reserved: 2023-08-07T13:02:25.476Z

Link: CVE-2023-4207

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Modified

Published: 2023-09-06T14:15:11.453

Modified: 2025-02-13T17:17:16.367

Link: CVE-2023-4207

cve-icon Redhat

Severity : Important

Publid Date: 2023-07-29T00:00:00Z

Links: CVE-2023-4207 - Bugzilla