Vulnerability in Linux
CVE-2023-53557
In the Linux kernel, the following vulnerability has been resolved: fprobe: Release rethook after the ftrace_ops is unregistered While running bpf selftests it's possible to get following fault: general protection fault, probably for non-canonical address \ 0x6b6b6b6b6b6b6b6b: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC NOPTI ... Call Trace: <TASK> fprobe_handler+0xc1/0x270 ? __pfx_bpf_testmod_init+0x10/0x10 ? __pfx_bpf_testmod_init+0x10/0x10 ? bpf_fentry_test1+0x5/0x10 ? bpf_fentry_test1+0x5/0x10 ? bpf_testmod_init+0x22/0x80 ? do_one_initcall+0x63/0x2e0 ? rcu_is_watching+0xd/0x40 ? kmalloc_trace+0xaf/0xc0 ? do_init_module+0x60/0x250 ? __do_sys_finit_module+0xac/0x120 ? do_syscall_64+0x37/0x90 ? entry_SYSCALL_64_after_hwframe+0x72/0xdc </TASK> In unregister_fprobe function we can't release fp->rethook while it's possible there are some of its users still running on another cpu. Moving rethook_free call after fp->ops is unregistered with unregister_ftrace_function call.
EPSS: 0.001 (3.3th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Linux — versions 5b0ab78998e32564a011b14c4c7f9c81e2d42b9d, 5.18, 0
- Linux Linux_kernel — versions 6.5
References
Frequently asked questions
- What is CVE-2023-53557?
- CVE-2023-53557 is a high-severity vulnerability in Linux. CVSS score: 7.8/10. Published 2025-10-04.
- How severe is CVE-2023-53557?
- High severity. CVSS v3 base score is 7.8 out of 10.