System crash via rearmed cxgb4 statistics timer
Published Aug 3, 2023 · Updated Nov 6, 2025
Use-after-free in the cxgb4 driver in Red Hat Enterprise Linux 8 and 9 allows local users to crash the system during device detach. The cxgb4_cleanup_tc_flower() path only synchronously deletes flower_stats_timer, while flower_stats_work can rearm it after teardown and later dereference the freed adapter. Reaching the flaw requires local privileges or physical access to remove or unbind a cxgb4 device, and the bounded consequence is a system crash.
Summary
What happened
Use-after-free in the cxgb4 driver in Red Hat Enterprise Linux 8 and 9 allows local users to crash the system during device detach. The cxgb4_cleanup_tc_flower() path only synchronously deletes flower_stats_timer, while flower_stats_work can rearm it after teardown and later dereference the freed adapter. Reaching the flaw requires local privileges or physical access to remove or unbind a cxgb4 device, and the bounded consequence is a system crash.
The record
- CVE
- CVE-2023-4133
- Published
- Aug 3, 2023
- Updated
- Nov 6, 2025
- Vendor
- Red Hat
- Product
- Red Hat Enterprise Linux 8
- Classifications
- CWE-416
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 3, 2023CVE publishedPublication date reported by the CVE source.
- Nov 6, 2025Record updatedLatest update available in the CVE record.
Exploitability
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Technologies
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