CVE-2025-21733

CVE-2025-21733 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Description

In the Linux kernel, the following vulnerability has been resolved: tracing/osnoise: Fix resetting of tracepoints If a timerlat tracer is started with the osnoise option OSNOISE_WORKLOAD disabled, but then that option is enabled and timerlat is removed, the tracepoints that were enabled on timerlat registration do not get disabled. If the option is disabled again and timelat is started, then it triggers a warning in the tracepoint code due to registering the tracepoint again without ever disabling it. Do not use the same user space defined options to know to disable the tracepoints when timerlat is removed. Instead, set a global flag when it is enabled and use that flag to know to disable the events. ~# echo NO_OSNOISE_WORKLOAD > /sys/kernel/tracing/osnoise/options ~# echo timerlat > /sys/kernel/tracing/current_tracer ~# echo OSNOISE_WORKLOAD > /sys/kernel/tracing/osnoise/options ~# echo nop > /sys/kernel/tracing/current_tracer ~# echo NO_OSNOISE_WORKLOAD > /sys/kernel/tracing/osnoise/options ~# echo timerlat > /sys/kernel/tracing/current_tracer Triggers: ------------[ cut here ]------------ WARNING: CPU: 6 PID: 1337 at kernel/tracepoint.c:294 tracepoint_add_func+0x3b6/0x3f0 Modules linked in: CPU: 6 UID: 0 PID: 1337 Comm: rtla Not tainted 6.13.0-rc4-test-00018-ga867c441128e-dirty #73 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:tracepoint_add_func+0x3b6/0x3f0 Code: 48 8b 53 28 48 8b 73 20 4c 89 04 24 e8 23 59 11 00 4c 8b 04 24 e9 36 fe ff ff 0f 0b b8 ea ff ff ff 45 84 e4 0f 84 68 fe ff ff <0f> 0b e9 61 fe ff ff 48 8b 7b 18 48 85 ff 0f 84 4f ff ff ff 49 8b RSP: 0018:ffffb9b003a87ca0 EFLAGS: 00010202 RAX: 00000000ffffffef RBX: ffffffff92f30860 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff9bf59e91ccd0 RDI: ffffffff913b6410 RBP: 000000000000000a R08: 00000000000005c7 R09: 0000000000000002 R10: ffffb9b003a87ce0 R11: 0000000000000002 R12: 0000000000000001 R13: ffffb9b003a87ce0 R14: ffffffffffffffef R15: 0000000000000008 FS: 00007fce81209240(0000) GS:ffff9bf6fdd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055e99b728000 CR3: 00000001277c0002 CR4: 0000000000172ef0 Call Trace: <TASK> ? __warn.cold+0xb7/0x14d ? tracepoint_add_func+0x3b6/0x3f0 ? report_bug+0xea/0x170 ? handle_bug+0x58/0x90 ? exc_invalid_op+0x17/0x70 ? asm_exc_invalid_op+0x1a/0x20 ? __pfx_trace_sched_migrate_callback+0x10/0x10 ? tracepoint_add_func+0x3b6/0x3f0 ? __pfx_trace_sched_migrate_callback+0x10/0x10 ? __pfx_trace_sched_migrate_callback+0x10/0x10 tracepoint_probe_register+0x78/0xb0 ? __pfx_trace_sched_migrate_callback+0x10/0x10 osnoise_workload_start+0x2b5/0x370 timerlat_tracer_init+0x76/0x1b0 tracing_set_tracer+0x244/0x400 tracing_set_trace_write+0xa0/0xe0 vfs_write+0xfc/0x570 ? do_sys_openat2+0x9c/0xe0 ksys_write+0x72/0xf0 do_syscall_64+0x79/0x1c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e

Frequently asked questions

What is CVE-2025-21733?
In the Linux kernel, the following vulnerability has been resolved: tracing/osnoise: Fix resetting of tracepoints If a timerlat tracer is started with the osnoise option OSNOISE_WORKLOAD disabled, but then that option is enabled and timerlat is removed, the tracepoints that were enabled on timerlat registration do not get disabled. If the option is disabled again and timelat is started, then it triggers a warning in the tracepoint code due to registering the tracepoint again without ever disabling it. Do not use the same user space defined options to know to disable the tracepoints when timerlat is removed. Instead, set a global flag when it is enabled and use that flag to know to disable the events. ~# echo NO_OSNOISE_WORKLOAD > /sys/kernel/tracing/osnoise/options ~# echo timerlat > /sys/kernel/tracing/current_tracer ~# echo OSNOISE_WORKLOAD > /sys/kernel/tracing/osnoise/options ~# echo nop > /sys/kernel/tracing/current_tracer ~# echo NO_OSNOISE_WORKLOAD > /sys/kernel/tracing/osnoise/options ~# echo timerlat > /sys/kernel/tracing/current_tracer Triggers: ------------[ cut here ]------------ WARNING: CPU: 6 PID: 1337 at kernel/tracepoint.c:294 tracepoint_add_func+0x3b6/0x3f0 Modules linked in: CPU: 6 UID: 0 PID: 1337 Comm: rtla Not tainted 6.13.0-rc4-test-00018-ga867c441128e-dirty #73 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:tracepoint_add_func+0x3b6/0x3f0 Code: 48 8b 53 28 48 8b 73 20 4c 89 04 24 e8 23 59 11 00 4c 8b 04 24 e9 36 fe ff ff 0f 0b b8 ea ff ff ff 45 84 e4 0f 84 68 fe ff ff <0f> 0b e9 61 fe ff ff 48 8b 7b 18 48 85 ff 0f 84 4f ff ff ff 49 8b RSP: 0018:ffffb9b003a87ca0 EFLAGS: 00010202 RAX: 00000000ffffffef RBX: ffffffff92f30860 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff9bf59e91ccd0 RDI: ffffffff913b6410 RBP: 000000000000000a R08: 00000000000005c7 R09: 0000000000000002 R10: ffffb9b003a87ce0 R11: 0000000000000002 R12: 0000000000000001 R13: ffffb9b003a87ce0 R14: ffffffffffffffef R15: 0000000000000008 FS: 00007fce81209240(0000) GS:ffff9bf6fdd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055e99b728000 CR3: 00000001277c0002 CR4: 0000000000172ef0 Call Trace: <TASK> ? __warn.cold+0xb7/0x14d ? tracepoint_add_func+0x3b6/0x3f0 ? report_bug+0xea/0x170 ? handle_bug+0x58/0x90 ? exc_invalid_op+0x17/0x70 ? asm_exc_invalid_op+0x1a/0x20 ? __pfx_trace_sched_migrate_callback+0x10/0x10 ? tracepoint_add_func+0x3b6/0x3f0 ? __pfx_trace_sched_migrate_callback+0x10/0x10 ? __pfx_trace_sched_migrate_callback+0x10/0x10 tracepoint_probe_register+0x78/0xb0 ? __pfx_trace_sched_migrate_callback+0x10/0x10 osnoise_workload_start+0x2b5/0x370 timerlat_tracer_init+0x76/0x1b0 tracing_set_tracer+0x244/0x400 tracing_set_trace_write+0xa0/0xe0 vfs_write+0xfc/0x570 ? do_sys_openat2+0x9c/0xe0 ksys_write+0x72/0xf0 do_syscall_64+0x79/0x1c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e
How severe is CVE-2025-21733?
CVE-2025-21733 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-21733 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-21733?
CVE-2025-21733 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-21733?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-21733 have an EU (EUVD) identifier?
Yes. CVE-2025-21733 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-5192.
When was CVE-2025-21733 published?
CVE-2025-21733 was published on 2025-02-27 and last updated on 2026-06-17.

References

Affected products (1)

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