CVE-2026-68283
tracing: Fix use-after-free freeing trigger private data
Description
In the Linux kernel, the following vulnerability has been resolved: tracing: Fix use-after-free freeing trigger private data Commit 61d445af0a7c ("tracing: Add bulk garbage collection of freeing event_trigger_data") moved the kfree() of event_trigger_data to a kthread that runs tracepoint_synchronize_unregister() before freeing. That removed the synchronization the trigger .free callbacks used to get implicitly and inline from trigger_data_free(). event_hist_trigger_free(), event_hist_trigger_named_free() and event_enable_trigger_free() free their satellite data (hist_data, cmd_ops, enable_data) right after trigger_data_free() returns. With the synchronization now deferred to the kthread, a concurrent tracepoint handler can still reach that data through the list_del_rcu()'d trigger, causing a use-after-free. The histogram teardown must stay synchronous: remove_hist_vars() and unregister_field_var_hists() have to detach a synthetic event from the histogram before the trigger-removal write returns, otherwise a following command races in and the synthetic-event removal fails with -EBUSY, as the trigger-synthetic-eprobe.tc selftest catches. Make those callbacks wait with the correct barrier - tracepoint_synchronize_unregister(), matching the free kthread - before freeing. The enable trigger has no such synchronous requirement, and a blocking synchronize there would re-serialize the path that commit deliberately deferred. Give it an optional private_data_free() callback that the free kthread runs after its grace period, and free enable_data from there.
INFO
Published Date :
Aug. 10, 2026, 1:20 p.m.
Last Modified :
Aug. 17, 2026, 5:18 a.m.
Remotely Exploit :
Yes !
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
Solution
- Update the Linux kernel to the patched version.
- Ensure the correct barrier is used before freeing data.
- Move optional callbacks to a deferred free kthread.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-68283.
| URL | Resource |
|---|---|
| https://git.kernel.org/stable/c/79097812153b826fc156a2930ec8a90ed9edf4a2 | |
| https://git.kernel.org/stable/c/b9c8a1400a3bf633f32820d184f3e05fed0f4af7 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-68283 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-68283
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-68283 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-68283 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 17, 2026
Action Type Old Value New Value Changed Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '61d445af0a7c70018111919e47beaaee15653f2f', 'lessThan': 'b9c8a1400a3bf633f32820d184f3e05fed0f4af7', 'versionType': 'git'}, {'status': 'affected', 'version': '61d445af0a7c70018111919e47beaaee15653f2f', 'lessThan': '79097812153b826fc156a2930ec8a90ed9edf4a2', 'versionType': 'git'}], 'programFiles': ['kernel/trace/trace.h', 'kernel/trace/trace_events_hist.c', 'kernel/trace/trace_events_trigger.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.19'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.19', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '7.1.6', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc5', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['kernel/trace/trace.h', 'kernel/trace/trace_events_hist.c', 'kernel/trace/trace_events_trigger.c'], 'defaultStatus': 'affected'}] [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '61d445af0a7c70018111919e47beaaee15653f2f', 'lessThan': 'b9c8a1400a3bf633f32820d184f3e05fed0f4af7', 'versionType': 'git'}, {'status': 'affected', 'version': '61d445af0a7c70018111919e47beaaee15653f2f', 'lessThan': '79097812153b826fc156a2930ec8a90ed9edf4a2', 'versionType': 'git'}], 'programFiles': ['kernel/trace/trace.h', 'kernel/trace/trace_events_hist.c', 'kernel/trace/trace_events_trigger.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.19'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.19', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '7.1.6', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['kernel/trace/trace.h', 'kernel/trace/trace_events_hist.c', 'kernel/trace/trace_events_trigger.c'], 'defaultStatus': 'affected'}] -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 13, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 10, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '61d445af0a7c70018111919e47beaaee15653f2f', 'lessThan': 'b9c8a1400a3bf633f32820d184f3e05fed0f4af7', 'versionType': 'git'}, {'status': 'affected', 'version': '61d445af0a7c70018111919e47beaaee15653f2f', 'lessThan': '79097812153b826fc156a2930ec8a90ed9edf4a2', 'versionType': 'git'}], 'programFiles': ['kernel/trace/trace.h', 'kernel/trace/trace_events_hist.c', 'kernel/trace/trace_events_trigger.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.19'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.19', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '7.1.6', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc5', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['kernel/trace/trace.h', 'kernel/trace/trace_events_hist.c', 'kernel/trace/trace_events_trigger.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: tracing: Fix use-after-free freeing trigger private data Commit 61d445af0a7c ("tracing: Add bulk garbage collection of freeing event_trigger_data") moved the kfree() of event_trigger_data to a kthread that runs tracepoint_synchronize_unregister() before freeing. That removed the synchronization the trigger .free callbacks used to get implicitly and inline from trigger_data_free(). event_hist_trigger_free(), event_hist_trigger_named_free() and event_enable_trigger_free() free their satellite data (hist_data, cmd_ops, enable_data) right after trigger_data_free() returns. With the synchronization now deferred to the kthread, a concurrent tracepoint handler can still reach that data through the list_del_rcu()'d trigger, causing a use-after-free. The histogram teardown must stay synchronous: remove_hist_vars() and unregister_field_var_hists() have to detach a synthetic event from the histogram before the trigger-removal write returns, otherwise a following command races in and the synthetic-event removal fails with -EBUSY, as the trigger-synthetic-eprobe.tc selftest catches. Make those callbacks wait with the correct barrier - tracepoint_synchronize_unregister(), matching the free kthread - before freeing. The enable trigger has no such synchronous requirement, and a blocking synchronize there would re-serialize the path that commit deliberately deferred. Give it an optional private_data_free() callback that the free kthread runs after its grace period, and free enable_data from there. Added Reference https://git.kernel.org/stable/c/79097812153b826fc156a2930ec8a90ed9edf4a2 Added Reference https://git.kernel.org/stable/c/b9c8a1400a3bf633f32820d184f3e05fed0f4af7