GHSA-J5FG-GWPM-PJW5
Vulnerability from github – Published: 2025-12-16 15:30 – Updated: 2025-12-16 15:30In the Linux kernel, the following vulnerability has been resolved:
ksmbd: ipc: fix use-after-free in ipc_msg_send_request
ipc_msg_send_request() waits for a generic netlink reply using an ipc_msg_table_entry on the stack. The generic netlink handler (handle_generic_event()/handle_response()) fills entry->response under ipc_msg_table_lock, but ipc_msg_send_request() used to validate and free entry->response without holding the same lock.
Under high concurrency this allows a race where handle_response() is copying data into entry->response while ipc_msg_send_request() has just freed it, leading to a slab-use-after-free reported by KASAN in handle_generic_event():
BUG: KASAN: slab-use-after-free in handle_generic_event+0x3c4/0x5f0 [ksmbd] Write of size 12 at addr ffff888198ee6e20 by task pool/109349 ... Freed by task: kvfree ipc_msg_send_request [ksmbd] ksmbd_rpc_open -> ksmbd_session_rpc_open [ksmbd]
Fix by: - Taking ipc_msg_table_lock in ipc_msg_send_request() while validating entry->response, freeing it when invalid, and removing the entry from ipc_msg_table. - Returning the final entry->response pointer to the caller only after the hash entry is removed under the lock. - Returning NULL in the error path, preserving the original API semantics.
This makes all accesses to entry->response consistent with handle_response(), which already updates and fills the response buffer under ipc_msg_table_lock, and closes the race that allowed the UAF.
{
"affected": [],
"aliases": [
"CVE-2025-68263"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-12-16T15:15:55Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: ipc: fix use-after-free in ipc_msg_send_request\n\nipc_msg_send_request() waits for a generic netlink reply using an\nipc_msg_table_entry on the stack. The generic netlink handler\n(handle_generic_event()/handle_response()) fills entry-\u003eresponse under\nipc_msg_table_lock, but ipc_msg_send_request() used to validate and free\nentry-\u003eresponse without holding the same lock.\n\nUnder high concurrency this allows a race where handle_response() is\ncopying data into entry-\u003eresponse while ipc_msg_send_request() has just\nfreed it, leading to a slab-use-after-free reported by KASAN in\nhandle_generic_event():\n\n BUG: KASAN: slab-use-after-free in handle_generic_event+0x3c4/0x5f0 [ksmbd]\n Write of size 12 at addr ffff888198ee6e20 by task pool/109349\n ...\n Freed by task:\n kvfree\n ipc_msg_send_request [ksmbd]\n ksmbd_rpc_open -\u003e ksmbd_session_rpc_open [ksmbd]\n\nFix by:\n- Taking ipc_msg_table_lock in ipc_msg_send_request() while validating\n entry-\u003eresponse, freeing it when invalid, and removing the entry from\n ipc_msg_table.\n- Returning the final entry-\u003eresponse pointer to the caller only after\n the hash entry is removed under the lock.\n- Returning NULL in the error path, preserving the original API\n semantics.\n\nThis makes all accesses to entry-\u003eresponse consistent with\nhandle_response(), which already updates and fills the response buffer\nunder ipc_msg_table_lock, and closes the race that allowed the UAF.",
"id": "GHSA-j5fg-gwpm-pjw5",
"modified": "2025-12-16T15:30:47Z",
"published": "2025-12-16T15:30:47Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-68263"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/1fab1fa091f5aa97265648b53ea031deedd26235"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/5ac763713a1ef8f9a8bda1dbd81f0318d67baa4e"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/759c8c30cfa8706c518e56f67971b1f0932f4b9b"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/8229c6ca50cea701e25a7ee25f48441b582ec5fa"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
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