CVE-2026-23240 (GCVE-0-2026-23240)
Vulnerability from cvelistv5
Published
2026-03-10 17:28
Modified
2026-10-19 18:35
Severity ?
9.8 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Summary
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
Impacted products
Vendor Product Version
Linux Linux Version: f87e62d45e51b12d48d2cb46b5cde8f83b866bc4
Version: f87e62d45e51b12d48d2cb46b5cde8f83b866bc4
Version: f87e62d45e51b12d48d2cb46b5cde8f83b866bc4
Version: f87e62d45e51b12d48d2cb46b5cde8f83b866bc4
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