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TI-2024-35655 Aliases CVE-2024-53186GHSA-w9v5-63v9-9qvj

ksmbd: fix use-after-free in SMB request handling

Priority MEDIUM 43CWE-416Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-416 and the CVSS impact.

Summary

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free in SMB request handling A race condition exists between SMB request handling in `ksmbd_conn_handler_loop()` and the freeing of `ksmbd_conn` in the workqueue handler `handle_ksmbd_work()`. This leads to a UAF. - KASAN: slab-use-after-free Read in handle_ksmbd_work - KASAN: slab-use-after-free in rtlock_slowlock_locked This race condition arises as follows: - `ksmbd_conn_handler_loop()` waits for `conn->r_count` to reach zero: `wait_event(conn->r_count_q, atomic_read(&conn->r_count) == 0);` - Meanwhile, `handle_ksmbd_work()` decrements `conn->r_count` using `atomic_dec_return(&conn->r_count)`, and if it reaches zero, calls `ksmbd_conn_free()`, which frees `conn`. - However, after `handle_ksmbd_work()` decrements `conn->r_count`, it may still access `conn->r_count_q` in the following line: `waitqueue_active(&conn->r_count_q)` or `wake_up(&conn->r_count_q)` This results in a UAF, as `conn` has already been freed. The discovery of this UAF can be referenced in the following PR for syzkaller's support for SMB requests.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00456 39th percentileScored 2026-11-07
Fix Fixed Linux (Linux): 6.6.64, 6.11.11, 6.11 +2

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux6.6.55 to before 6.6.64; 6.11.3 to before 6.11.11; 6.10.14 to before 6.116.6.64, 6.11.11, 6.11Patch availableCNA
LinuxLinux6.12 and later6.6.64, 6.11.11, 6.12.2, 6.13Patch availableCNA
  • Linux VendorLinux Affected 6.6.55 to before 6.6.64; 6.11.3 to before 6.11.11; 6.10.14 to before 6.11 Fixed in 6.6.64, 6.11.11, 6.11 Patch available CNA
  • Linux VendorLinux Affected 6.12 and later Fixed in 6.6.64, 6.11.11, 6.12.2, 6.13 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*6.6.55 to before 6.6.64; 6.10.14 to before 6.11; 6.11.3 to before 6.11.11; 6.12 to before 6.12.2VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 6.6.55 to before 6.6.64; 6.10.14 to before 6.11; 6.11.3 to before 6.11.11; 6.12 to before 6.12.2 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 6.6.64, 6.11.11, 6.11
  • Fix · CNA Linux (Linux) Fixed in 6.6.64, 6.11.11, 6.12.2, 6.13

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

Not affected: 4 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2024-53186
  2. 2026-10-03 Alias added: GHSA-w9v5-63v9-9qvj

References

Patch 4

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
  • TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
See all 15278 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences