Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2024-53176— smb: During unmount, ensure all cached dir instances drop their dentry

Quick assessment

Affected
Linux Linux
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Linux kernel是美国Linux基金会的开源操作系统Linux所使用的内核。 Linux kernel存在安全漏洞，该漏洞源于smb子系统中在卸载过程中未能确保所有缓存目录实例释放它们的dentry。

CVSS 9.8 · Critical EPSS 0.56% · P45

Possible ATT&CK Techniques 1 AI

T1499 · Endpoint Denial of Service

Affected Version Matrix 10

VendorProduct Version RangeStatus
Linux Linux ebe98f1447bbccf8228335c62d86af02a0ed23f7< 73934e535cffbda1490fa97d82690a0f9aa73e94 affected
ebe98f1447bbccf8228335c62d86af02a0ed23f7< ff4528bbc82d0d90073751f7b49e7b9e9c7e5638 affected
ebe98f1447bbccf8228335c62d86af02a0ed23f7< 548812afd96982a76a93ba76c0582ea670c40d9e affected
ebe98f1447bbccf8228335c62d86af02a0ed23f7< 3fa640d035e5ae526769615c35cb9ed4be6e3662 affected
6.1 affected
< 6.1 unaffected
6.6.64≤ 6.6.* unaffected
6.11.11≤ 6.11.* unaffected
… +2 more rows
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2024-53176

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
smb: During unmount, ensure all cached dir instances drop their dentry
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: smb: During unmount, ensure all cached dir instances drop their dentry The unmount process (cifs_kill_sb() calling close_all_cached_dirs()) can race with various cached directory operations, which ultimately results in dentries not being dropped and these kernel BUGs: BUG: Dentry ffff88814f37e358{i=1000000000080,n=/} still in use (2) [unmount of cifs cifs] VFS: Busy inodes after unmount of cifs (cifs) ------------[ cut here ]------------ kernel BUG at fs/super.c:661! This happens when a cfid is in the process of being cleaned up when, and has been removed from the cfids->entries list, including: - Receiving a lease break from the server - Server reconnection triggers invalidate_all_cached_dirs(), which removes all the cfids from the list - The laundromat thread decides to expire an old cfid. To solve these problems, dropping the dentry is done in queued work done in a newly-added cfid_put_wq workqueue, and close_all_cached_dirs() flushes that workqueue after it drops all the dentries of which it's aware. This is a global workqueue (rather than scoped to a mount), but the queued work is minimal. The final cleanup work for cleaning up a cfid is performed via work queued in the serverclose_wq workqueue; this is done separate from dropping the dentries so that close_all_cached_dirs() doesn't block on any server operations. Both of these queued works expect to invoked with a cfid reference and a tcon reference to avoid those objects from being freed while the work is ongoing. While we're here, add proper locking to close_all_cached_dirs(), and locking around the freeing of cfid->dentry.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
N/A
Source: CVE Program / CVE List V5
Vulnerability Title
Linux kernel 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Linux kernel是美国Linux基金会的开源操作系统Linux所使用的内核。 Linux kernel存在安全漏洞，该漏洞源于smb子系统中在卸载过程中未能确保所有缓存目录实例释放它们的dentry。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
Linux Linux ebe98f1447bbccf8228335c62d86af02a0ed23f7 ~ 73934e535cffbda1490fa97d82690a0f9aa73e94 -
Linux Linux 6.1 -

II. Public POCs for CVE-2024-53176

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2024-53176

请登录查看更多情报信息。

Patches & Fixes for CVE-2024-53176 (4)

Same Patch Batch · Linux · 2024-12-27 · 221 CVEs total

CVE-2024-53186 9.8 CRITICAL ksmbd: fix use-after-free in SMB request handling
CVE-2024-53179 9.8 CRITICAL smb: client: fix use-after-free of signing key
CVE-2024-53169 9.8 CRITICAL nvme-fabrics: fix kernel crash while shutting down controller
CVE-2024-56645 9.8 CRITICAL can: j1939: j1939_session_new(): fix skb reference counting
CVE-2024-53209 9.8 CRITICAL bnxt_en: Fix receive ring space parameters when XDP is active
CVE-2024-56656 9.8 CRITICAL bnxt_en: Fix aggregation ID mask to prevent oops on 5760X chips
CVE-2024-53177 9.8 CRITICAL smb: prevent use-after-free due to open_cached_dir error paths
CVE-2024-53206 9.8 CRITICAL tcp: Fix use-after-free of nreq in reqsk_timer_handler().
CVE-2024-56640 9.8 CRITICAL net/smc: fix LGR and link use-after-free issue
CVE-2024-56591 8.8 HIGH Bluetooth: hci_conn: Use disable_delayed_work_sync
CVE-2024-56626 8.8 HIGH ksmbd: fix Out-of-Bounds Write in ksmbd_vfs_stream_write
CVE-2024-56669 8.8 HIGH iommu/vt-d: Remove cache tags before disabling ATS
CVE-2024-53237 8.8 HIGH Bluetooth: fix use-after-free in device_for_each_child()
CVE-2024-53224 8.8 HIGH RDMA/mlx5: Move events notifier registration to be after device registration
CVE-2024-56653 8.8 HIGH Bluetooth: btmtk: avoid UAF in btmtk_process_coredump
CVE-2024-56651 8.8 HIGH can: hi311x: hi3110_can_ist(): fix potential use-after-free
CVE-2024-56627 8.1 HIGH ksmbd: fix Out-of-Bounds Read in ksmbd_vfs_stream_read
CVE-2024-56538 7.8 HIGH drm: zynqmp_kms: Unplug DRM device before removal
CVE-2024-56624 7.8 HIGH iommufd: Fix out_fput in iommufd_fault_alloc()
CVE-2024-56628 7.8 HIGH LoongArch: Add architecture specific huge_pte_clear()

Showing top 20 of 221 CVEs. View all on vendor page &rarr; →

IV. Related Vulnerabilities

Same product: Linux
Same vendor: Linux

V. Comments for CVE-2024-53176

No comments yet

Leave a comment