Answer in brief
CVE-2025-40039 records a High severity (CVSS 8.8) vulnerability in ksmbd: Fix race condition in RPC handle list access. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 8.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Product | Affected versions | Fixed versions |
|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | Not reported | Not reported |
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=a4348710a7267705b75692dc1a000920481d1d92 <69674b029002b1d90b655f014bdf64f404efa54d || >=b685757c7b08d5073046fb379be965fd6c06aafc <6b615a8fb3af0baf8126cde3d4fee97d57222ffc || >=b685757c7b08d5073046fb379be965fd6c06aafc <5cc679ba0f4505936124cd4179ba66bb0a4bd9f3 || >=b685757c7b08d5073046fb379be965fd6c06aafc <6bd7e0e55dcea2cf0d391bbc21c2eb069b4be3e1 || >=b685757c7b08d5073046fb379be965fd6c06aafc <305853cce379407090a73b38c5de5ba748893aee || 1f485b54d04a920723984062c912174330a05178 || 052b41ef2abe274f068e892aee81406f11bd1f3a || >=5.15.145 <5.16 | 69674b029002b1d90b655f014bdf64f404efa54d, 6b615a8fb3af0baf8126cde3d4fee97d57222ffc, 5cc679ba0f4505936124cd4179ba66bb0a4bd9f3, 6bd7e0e55dcea2cf0d391bbc21c2eb069b4be3e1, 305853cce379407090a73b38c5de5ba748893aee, 5.16 |
| Linux/Linuxgeneric | 6.3 | Not reported |
Published upstream
Oct 28, 2025
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 19, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
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.
Quoted source text, attributed separately from HOL analysis.