Vulnerability record · CVE-2026-89536 · published 11 September 2026
CVE-2026-89536: In the Linux kernel, the following vulnerability has been resolved: SUNRPC: wait for in-flight client TLS han…
In the Linux kernel, the following vulnerability has been resolved: SUNRPC: wait for in-flight client TLS handshake callback xs_tls_handshake_sync() gives xs_tls_handshake_done() a reference to the lower transport before submitting the handshake request. On timeout or signal, the synchronous waiter drops that reference after calling tls_handshake_cancel(). handshake_req_cancel() returns false when handshake_complete() has already marked the request complete. In that case the completion callback can still be running, so dropping the callback-owned reference in the waiter can free the lower transport before xs_tls_handshake_done() stores xprt_err or drops its own reference. If cancellation loses to completion, wait until xs_tls_handshake_done() signals handshake_done and let the callback release its reference. This mirrors the server-side handshake lifetime handling and keeps the timeout or signal return value unchanged.
Description
In the Linux kernel, the following vulnerability has been resolved: SUNRPC: wait for in-flight client TLS handshake callback xs_tls_handshake_sync() gives xs_tls_handshake_done() a reference to the lower transport before submitting the handshake request. On timeout or signal, the synchronous waiter drops that reference after calling tls_handshake_cancel(). handshake_req_cancel() returns false when handshake_complete() has already marked the request complete. In that case the completion callback can still be running, so dropping the callback-owned reference in the waiter can free the lower transport before xs_tls_handshake_done() stores xprt_err or drops its own reference. If cancellation loses to completion, wait until xs_tls_handshake_done() signals handshake_done and let the callback release its reference. This mirrors the server-side handshake lifetime handling and keeps the timeout or signal return value unchanged.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
References
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Source: NIST National Vulnerability Database (record CVE-2026-89536), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.
