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CVE-2026-93121— usb: gadget: f_fs: Fix fence cleanup in ffs_dmabuf_transfer() error paths

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.

在 Linux 内核中,已修复以下漏洞: usb: gadget: f_fs: 修复 ffs_dmabuf_transfer() 错误路径中的 fence 清理逻辑 在 中,当端点处于禁用状态(ESHUTDOWN)或请求分配失败(ENOMEM)时,控制流会跳转到 标签,该标签会调用 来释放 fence。然而,此时 fence 仅通过 分配,尚未调用 ,因此其引用计数(refcount)和 fence 操作结构体(fence ops)均未初始化。对这样一个未初始化的对象调用 会导致未定义行为。 因此,应改用 来释放该

CVSS 7.0 · High EPSS 0.15% · P4

Possible ATT&CK Techniques 1 AI

T1203 · Exploitation for Client Execution

Affected Version Matrix 10

VendorProduct Version RangeStatus
Linux Linux 7b07a2a7ca02a20124b552be96c5a56910795488< be539138d9a187af3b884525a395db10797c64f1 affected
7b07a2a7ca02a20124b552be96c5a56910795488< 5fd8baacc7dc477df9cac61b45491840247a9b1e affected
7b07a2a7ca02a20124b552be96c5a56910795488< 58952c83dfe6ea3294a74734d2d1018c1120779a affected
7b07a2a7ca02a20124b552be96c5a56910795488< 621707dc67c9846fd876d7579ec951d92aa033f1 affected
6.9 affected
< 6.9 unaffected
6.12.110≤ 6.12.* unaffected
6.18.52≤ 6.18.* unaffected
… +2 more rows
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I. Basic Information for CVE-2026-93121

Vulnerability Information

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Vulnerability Title
usb: gadget: f_fs: Fix fence cleanup in ffs_dmabuf_transfer() error paths
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_fs: Fix fence cleanup in ffs_dmabuf_transfer() error paths The error paths for endpoint-disabled (ESHUTDOWN) and request-allocation failure (ENOMEM) in ffs_dmabuf_transfer() jump to err_fence_put which calls dma_fence_put() on the fence. However, at that point the fence has only been kmalloc'd — dma_fence_init() has not been called yet, so the refcount and the fence ops are uninitialized. Calling dma_fence_put() on such an object leads to undefined behavior. Use kfree() instead, since the fence is just a plain allocation at this stage, and rename the label to err_fence_free to reflect the actual cleanup action.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:L/AC:H/PR:L/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

Affected Products

Vendor Product Affected Versions CPE Subscribe
Linux Linux 7b07a2a7ca02a20124b552be96c5a56910795488 ~ be539138d9a187af3b884525a395db10797c64f1 -
Linux Linux 6.9 -

II. Public POCs for CVE-2026-93121

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III. Intelligence Information for CVE-2026-93121

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Patches & Fixes for CVE-2026-93121 (4)

Same Patch Batch · Linux · 2026-09-17 · 600 CVEs total

CVE-2026-92489 9.8 CRITICAL xfrm: Fix skb double-free in xfrm_dev_direct_output()
CVE-2026-90151 9.8 CRITICAL NFSv4: remove callback IDR entry on client allocation failure
CVE-2026-90235 9.8 CRITICAL sunrpc: xprtsock: annotate shared socket callbacks with READ_ONCE/WRITE_ONCE
CVE-2026-90104 9.8 CRITICAL NFSv4.1: zero referring call lists before decoding
CVE-2026-90173 9.8 CRITICAL smb: smbdirect: free completion queues with ib_free_cq()
CVE-2026-90110 9.4 CRITICAL inetpeer: randomize RB-tree node comparison using SipHash
CVE-2026-90230 9.1 CRITICAL nvmet: fix heap out-of-bounds read in nvmet_auth_negotiate()
CVE-2026-90413 9.1 CRITICAL IB/isert: reject login PDUs declaring more data than was received
CVE-2026-90414 9.1 CRITICAL IB/isert: reject PDUs declaring more data than was received
CVE-2026-90425 8.8 HIGH iommu/tegra241-cmdqv: Require exactly one Stream ID for a vSID
CVE-2026-93042 8.8 HIGH dmaengine: dw-edma: Terminate all descriptors without callbacks
CVE-2026-93189 8.8 HIGH HID: core: quiesce input in hid_hw_stop() to prevent use-after-free
CVE-2026-90329 8.8 HIGH HID: synchronize input before cleaning up a failed probe
CVE-2026-90357 8.8 HIGH wifi: mt76: mt7915: unlink TWT flow if the MCU rejects the agreement
CVE-2026-90256 8.8 HIGH Bluetooth: L2CAP: use proto_lock for l2cap_data to fix l2cap_disconn_ind
CVE-2026-90367 8.8 HIGH wifi: mt76: mt7996: hold dev->mt76.mutex while disabling tx worker in SER
CVE-2026-90381 8.8 HIGH wifi: mt76: fix handling channel context with different bands in mt76_switch_vif_chanctx()
CVE-2026-90379 8.8 HIGH wifi: mt76: mt7921: Add PCIe AER handler support to prevent system crash
CVE-2026-90380 8.8 HIGH wifi: mt76: mt792x: fix use-after-free in mt76_rx_poll_complete
CVE-2026-90371 8.8 HIGH wifi: mt76: fix RXDMAD_C buffer recycling race

Showing top 20 of 600 CVEs. View all on vendor page &rarr; →

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