CVE-2026-64402
In the Linux kernel, the following vulnerability has been resolved: coresight: ultrasoc-smb: Fix OOB write in smb_sync_perf_buffer() When the SMB sink is used as a perf AUX sink, smb_update_buffer() calls smb_sync_perf_buffer() to copy hardware trace data into the perf AUX ring buffer pages. It derives pg_idx = head >> PAGE_SHIFT from @head, which is handle->head, and indexes dst_pages[pg_idx]. The pg_idx %= nr_pages normalization is only applied after the first loop iteration. This leaves the initial page index underived from the buffer size, which can result in an out-of-bounds write past dst_pages[] when head exceeds the AUX buffer size. Normalize head modulo the AUX buffer size before deriving the page index and offset, mirroring tmc_etr_sync_perf_buffer().
Affected versions
Linux kernel versions
6.3
and later are affected. Fixed in
6.6.145,
6.12.96,
6.18.39,
7.1.4,
7.2-rc1
and their respective stable series.
References
5 totalFrequently asked questions
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What is CVE-2026-64402?
CVE-2026-64402 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 6.3 onward and has been patched in 6.6.145, 6.12.96, 6.18.39 and others. CVE-2026-64402 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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Is there a patch available for CVE-2026-64402?
Yes. CVE-2026-64402 has been patched. Fixed versions include 6.6.145, 6.12.96, 6.18.39 and others. If you are running Linux kernel 6.3 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-64402 actively exploited?
No. CVE-2026-64402 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.