CVE-2026-23239: espintcp: Fix race condition in espintcp_close()

Vulnerability summary

CVE-2026-23239 is a high (CVSS 7.8) vulnerability in linux. EPSS estimates a 0.12% chance of exploitation in the next 30 days, higher than 2% of scored vulnerabilities.

Timeline

1. 10-03-2026
   PublishedVulnerability first disclosed.
2. 19-10-2026
   Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: espintcp: Fix race condition in espintcp_close() This issue was discovered during a code audit. After cancel_work_sync() is called from espintcp_close(), espintcp_tx_work() can still be scheduled from paths such as the Delayed ACK handler or ksoftirqd. As a result, the espintcp_tx_work() worker may dereference a freed espintcp ctx or sk. The following is a simple race scenario: cpu0 cpu1 espintcp_close() cancel_work_sync(&ctx->work); espintcp_write_space() schedule_work(&ctx->work); To prevent this race condition, cancel_work_sync() is replaced with disable_work_sync().

• CWE-362Concurrent Execution using Shared Resource with Improper SynchronizationThe product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.