VulnerabilityPublished 17 Sep 2026Updated 19 Oct 2026

CVE-2026-93120: Linux kernel · usb: gadget: configfs: fix out-of-bounds read of qw_sign

Affects Linux kernelSource CVE Database V5

Not known to be exploited · fixed in f63edb54d8f738f9c21e2068c777ae1c097df6b7 : update Linux kernel when convenient.

Data as of 27 Oct 2026, 05:11 UTC

Severity

Medium

Rated Medium by Threat Radar's AI analysis · CVSS not yet scored by NVD

EPSS: 0.2% chance of exploitation in 30 days – higher than 11% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in f63edb54d8f738f9c21e2068c777ae1c097df6b7, f6da500b0f8106882598b6dec87fe37d653946cf, b895dbed8ac9e12a5ffa1a2165575a8469f8340d +5

Exploitation evidence

Disclosed: evidence found.
CVE published 17 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by 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.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected ≥ 76180d716f91f035d9c8639497cf5459b44e1a51, < f63edb54d8f738f9c21e2068c777ae1c097df6b7	Fixed in f63edb54d8f738f9c21e2068c777ae1c097df6b7
LinuxLinux	Affected ≥ 76180d716f91f035d9c8639497cf5459b44e1a51, < f6da500b0f8106882598b6dec87fe37d653946cf	Fixed in f6da500b0f8106882598b6dec87fe37d653946cf
LinuxLinux	Affected ≥ 76180d716f91f035d9c8639497cf5459b44e1a51, < b895dbed8ac9e12a5ffa1a2165575a8469f8340d	Fixed in b895dbed8ac9e12a5ffa1a2165575a8469f8340d
LinuxLinux	Affected ≥ 76180d716f91f035d9c8639497cf5459b44e1a51, < afbf39c0f2297c6abef6d670a82a2079b0836191	Fixed in afbf39c0f2297c6abef6d670a82a2079b0836191
LinuxLinux	Affected ≥ 76180d716f91f035d9c8639497cf5459b44e1a51, < a28c486434634f6d1e120711d2b09f3eddea6c98	Fixed in a28c486434634f6d1e120711d2b09f3eddea6c98
LinuxLinux	Affected ≥ 76180d716f91f035d9c8639497cf5459b44e1a51, < 36315a330e067f7773196940552feacb1debbef1	Fixed in 36315a330e067f7773196940552feacb1debbef1

AI-suggested

A fix for this vulnerability has been implemented and is available in the referenced Linux kernel commits. Users should update to a kernel version that includes these fixes. Since this is a kernel vulnerability, applying the official patch or upgrading to a fixed kernel release is the recommended mitigation.

Description

A vulnerability in the Linux kernel's USB gadget configfs interface allows an out-of-bounds read of the qw_sign array. The flaw arises because the length argument passed to a UTF-16 to UTF-8 conversion function incorrectly counts bytes instead of UTF-16 code units, causing reads beyond the array boundary. This can expose adjacent memory bytes through the configfs attribute when the stored signature lacks a NUL terminator. The issue has been fixed in several commits.

Impact

The vulnerability allows an out-of-bounds read that can leak memory contents adjacent to the qw_sign array in the kernel's gadget_info structure. This exposure occurs through the configfs interface, potentially revealing sensitive kernel memory data to local users with access to this interface. There is no indication of code execution or privilege escalation. No known exploits in the wild have been reported.

Summary

CVE-2026-93120 is an out-of-bounds read vulnerability in the Linux kernel's usb gadget configfs code. The function os_desc_qw_sign_show() incorrectly passes the byte size of the qw_sign array as the length parameter to utf16s_to_utf8s(), which expects a count of UTF-16 code units. Since qw_sign holds half as many code units as bytes, this results in reading up to 14 bytes past the end of the array into adjacent struct gadget_info members. This memory is then exposed via the configfs attribute if the signature fills the array without a terminating NUL. The store path also mishandles length parameters but was corrected to use consistent code-unit counts. Multiple commits have fixed this issue.

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 26 Oct 2026, 14:34 UTC

Technical details

References

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