Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
AV AC PR UI S C I A CVSS EPSS %ile KEV L H L N U N N H 4.7 .0030 22.8 —
AFFECTED Product Versions Fixed Linux a4348710a7267705b75692dc1a000920481d1d92 – — Linux 6.3 – 6.6.123
TIMELINE Apr 16 Reserved by Linux Oct 28 Published (CNA: Linux) Jul 30 RESCORED — CVE-2025-40039 (Linux). CVSS 8.8 → 4.7 (NVD).
In the Linux kernel, the following vulnerability has been resolved: ksmbd: Fix race condition in RPC handle list access The 'sess->rpc_handle_list' XArray manages RPC handles within a ksmbd session. Access to this list is intended to be protected by 'sess->rpc_lock' (an rw_semaphore). However, the locking implementation was flawed, leading to potential race conditions. In ksmbd_session_rpc_open(), the code incorrectly acquired only a read lock before calling xa_store() and xa_erase(). Since these operations modify the XArray structure, a write lock is required to ensure exclusive access and prevent data corruption from concurrent modifications. Furthermore, ksmbd_session_rpc_method() accessed the list using xa_load() without holding any lock at all. This could lead to reading inconsistent data or a potential use-after-free if an entry is concurrently removed and the pointer is dereferenced. Fix these issues by: 1. Using down_write() and up_write() in ksmbd_session_rpc_open() to ensure exclusive access during XArray modification, and ensuring the lock is correctly released on error paths. 2. Adding down_read() and up_read() in ksmbd_session_rpc_method() to safely protect the lookup.
| Date | Event | Detail |
|---|---|---|
| April 16, 2025 | Reserved | Reserved by Linux |
| October 28, 2025 | Published | Published (CNA: Linux) |
| July 30, 2026 | RESCORED | RESCORED — CVE-2025-40039 (Linux). CVSS 8.8 → 4.7 (NVD). |
Authoritative record: CVE-2025-40039 at cve.org
Vendors: linux
Weaknesses: CWE-362
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2025-40039 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.