# CVE-2026-68283: linux: In the Linux kernel, the following vulnerability has been resolved:  tracing: Fix use-after-free freeing trigger priv...

CVE-2026-68283 is fixed in linux on 1 platform by DEBIAN-CVE-2026-68283 (version 7.1.6-1), released August 11, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-68283
- Priority: High
- CVSS: 8.8 (high)
- EPSS: 0.0037
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 10, 2026

## 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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 14 | 7.1.6-1 | [DEBIAN-CVE-2026-68283](https://patchblox.com/security/data/fix/linux/debian-cve-2026-68283.md) | Aug 11, 2026 |

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Data as of 2026-11-08T13:06:02Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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