In the Linux kernel, the following vulnerability has been resolved:

tcp: Fix potential UAF in reqsk_timer_handler().

When TCP socket migration fails at inet_ehash_insert() in
reqsk_timer_handler(), we jump to the no_ownership: label
and free the new reqsk immediately with __reqsk_free().

Thus, we must stop the new reqsk's timer before jumping to the
label, but the timer might be missed since the cited commit,
resulting in UAF.

As we are in the original reqsk's timer context, we can safely
call timer_delete_sync() for the new reqsk.

Let's pass false to __inet_csk_reqsk_queue_drop() to stop
the new reqsk's timer.

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Tue, 03 Nov 2026 12:45:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: tcp: Fix potential UAF in reqsk_timer_handler(). When TCP socket migration fails at inet_ehash_insert() in reqsk_timer_handler(), we jump to the no_ownership: label and free the new reqsk immediately with __reqsk_free(). Thus, we must stop the new reqsk's timer before jumping to the label, but the timer might be missed since the cited commit, resulting in UAF. As we are in the original reqsk's timer context, we can safely call timer_delete_sync() for the new reqsk. Let's pass false to __inet_csk_reqsk_queue_drop() to stop the new reqsk's timer.
Title tcp: Fix potential UAF in reqsk_timer_handler().
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
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cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-11-03T12:32:09.364Z

Reserved: 2026-09-25T10:25:14.404Z

Link: CVE-2026-99270

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-11-03T13:17:24.097

Modified: 2026-11-03T13:17:24.097

Link: CVE-2026-99270

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

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