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VulnerabilityPublished Updated

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

Affects Linux kernelSource CVE Database V5

0

Not known to be exploited · CVSS 7.0 High · fixed in be539138d9a187af3b884525a395db10797c64f1 : patch Linux kernel soon.

Data as of 26 Oct 2026, 17:16 UTC

CVSS 3.1 base score
7.0High
How severe the flaw is on the 0–10 CVSS scale.
EPSS
0.1% chance of exploitation in 30 days – higher than 4% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch
Available – fixed in be539138d9a187af3b884525a395db10797c64f1, 621707dc67c9846fd876d7579ec951d92aa033f1, 58952c83dfe6ea3294a74734d2d1018c1120779a +1
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 17 Sep 2026

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponised: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq Mirage: no evidence on record.

    No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

What to do

Upgrade Linux kernel to be539138d9a187af3b884525a395db10797c64f1, 621707dc67c9846fd876d7579ec951d92aa033f1, 58952c83dfe6ea3294a74734d2d1018c1120779a or 5fd8baacc7dc477df9cac61b45491840247a9b1e.

Affected software

ProductAffectedFixed in
LinuxLinuxAffected
  • ≥ 7b07a2a7ca02a20124b552be96c5a56910795488, < be539138d9a187af3b884525a395db10797c64f1
Fixed in
  • be539138d9a187af3b884525a395db10797c64f1
LinuxLinuxAffected
  • ≥ 7b07a2a7ca02a20124b552be96c5a56910795488, < 621707dc67c9846fd876d7579ec951d92aa033f1
Fixed in
  • 621707dc67c9846fd876d7579ec951d92aa033f1
LinuxLinuxAffected
  • ≥ 7b07a2a7ca02a20124b552be96c5a56910795488, < 58952c83dfe6ea3294a74734d2d1018c1120779a
Fixed in
  • 58952c83dfe6ea3294a74734d2d1018c1120779a
LinuxLinuxAffected
  • ≥ 7b07a2a7ca02a20124b552be96c5a56910795488, < 5fd8baacc7dc477df9cac61b45491840247a9b1e
Fixed in
  • 5fd8baacc7dc477df9cac61b45491840247a9b1e
LinuxLinuxAffected
  • =6.9
Fixed in–

AI-suggested

A fix is available and has been applied in Linux kernel version 6.9 and specific commits. Users and administrators should update to the fixed kernel versions to remediate this vulnerability. No additional mitigation steps are indicated beyond applying the official patch.

Description

CVE-2026-93121 is a high-severity vulnerability in the Linux kernel's USB gadget function f_fs. It involves improper cleanup of a dma_fence object in error paths of the ffs_dmabuf_transfer() function. Specifically, dma_fence_put() was called on a fence that had only been allocated but not fully initialized, leading to undefined behavior. This issue has been fixed by replacing dma_fence_put() with kfree() for cleanup in these error cases.

References

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