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CVE-2025-68263 (GCVE-0-2025-68263)

Vulnerability from cvelistv5 – Published: 2025-12-16 14:45 – Updated: 2026-08-05 12:10
VLAI
Title
ksmbd: ipc: fix use-after-free in ipc_msg_send_request
Summary
In 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.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < de85fb58f9967ba024bb08e0041613d37b57b4d1 (git)
Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 708a620b471a14466f1f52c90bf3f65ebdb31460 (git)
Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 5ac763713a1ef8f9a8bda1dbd81f0318d67baa4e (git)
Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 759c8c30cfa8706c518e56f67971b1f0932f4b9b (git)
Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 8229c6ca50cea701e25a7ee25f48441b582ec5fa (git)
Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 1fab1fa091f5aa97265648b53ea031deedd26235 (git)
guessed Create a notification for this product.
Linux Linux Affected: 5.15
Unaffected: 0 , < 5.15 (semver)
Unaffected: 6.1.160 , ≤ 6.1.* (semver)
Unaffected: 6.6.120 , ≤ 6.6.* (semver)
Unaffected: 6.12.62 , ≤ 6.12.* (semver)
Unaffected: 6.17.12 , ≤ 6.17.* (semver)
Unaffected: 6.18.1 , ≤ 6.18.* (semver)
Unaffected: 6.19 , ≤ * (original_commit_for_fix)
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              "value": "ksmbd IPC message use-after-free. The race in ipc_msg_send_request() is reachable from ksmbd_ipc_login_request() called during SESSION_SETUP before password verification. Two concurrent SESSION_SETUP requests with any username trigger concurrent IPC calls that race. No valid credentials needed, both sides attacker-controlled."
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      "cve": "CVE-2025-68263",
      "id": "CVE-2025-68263",
      "initial_release_date": "2025-12-16T00:00:00+00:00",
      "product_status:known_not_affected": "274",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: Linux kernel ksmbd: Use-after-free vulnerability allows arbitrary code execution",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-68263.json",
      "version": "3"
    },
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      "aggregate_severity": "moderate",
      "current_release_date": "2026-08-29T01:12:29Z",
      "cve": "CVE-2025-68263",
      "id": "CVE-2025-68263",
      "initial_release_date": "2025-12-17T00:24:04Z",
      "product_status:known_not_affected": "538",
      "product_status:recommended": "6",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2025-68263",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2025-68263.json",
      "version": "18"
    }
  }
}



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