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

tls: Fix race condition in tls_sw_cancel_work_tx()

This issue was discovered during a code audit.

After cancel_delayed_work_sync() is called from tls_sk_proto_close(),
tx_work_handler() can still be scheduled from paths such as the
Delayed ACK handler or ksoftirqd.
As a result, the tx_work_handler() worker may dereference a freed
TLS object.

The following is a simple race scenario:

      cpu0                         cpu1

tls_sk_proto_close()
tls_sw_cancel_work_tx()
tls_write_space()
tls_sw_write_space()
if (!test_and_set_bit(BIT_TX_SCHEDULED, &tx_ctx->tx_bitmask))
set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask);
cancel_delayed_work_sync(&ctx->tx_work.work);
schedule_delayed_work(&tx_ctx->tx_work.work, 0);

To prevent this race condition, cancel_delayed_work_sync() is
replaced with disable_delayed_work_sync().

References

• https://nvd.nist.gov/vuln/detail/CVE-2026-23240
• https://git.kernel.org/stable/c/17153f154f80be2b47ebf52840f2d8f724eb2f3b
• https://git.kernel.org/stable/c/7bb09315f93dce6acc54bf59e5a95ba7365c2be4
• https://git.kernel.org/stable/c/854cd32bc74fe573353095e90958490e4e4d641b
• https://git.kernel.org/stable/c/a5de36d6cee74a92c1a21b260bc507e64bc451de