Vulnerability Report

CVE-2026-31720

RCE

Title: Linux kernel USB Gadget Stack Out-of-Bounds Write

RCE

Proof Of Concept

PoC Available for CVE-2026-31720

CWE Category CWE-787

Published Date May 01, 2026

Modified Date May 06, 2026

Exploit Status Available

Score 7.8 CVSS v3.1

Exploit Probability (EPSS)

0.18%

Vulnerability Summary

CVE-2026-31720: In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_uac1_legacy: validate control request size f_audio_complete() copies req->length bytes into a 4-byte stack variable: u32 data = 0; memcpy(&data, req->buf, req->length); req->length is derived from the host-controlled USB request path, which can lead to a stack out-of-bounds write. Validate req->actual against the expected payload size for the supported control selectors and decode only the expected amount of data. This avoids copying a host-influenced length into a fixed-size stack object.

Impacted Vendors

linux 1

ubuntu 1

Reference Links

https://git.kernel.org/stable/c/0d41772d98dcaf6c17e875b7d0ea0154ae1191ee https://git.kernel.org/stable/c/21b11e8581285c6f10ef43d05df349d445f24273 https://git.kernel.org/stable/c/26304d124e7f0383f8fe1168b5801a0ac7e16b1c https://git.kernel.org/stable/c/557d1d4e862eccd0b74cc377b66de3e1e8d49605 https://git.kernel.org/stable/c/6e0e34d85cd46ceb37d16054e97a373a32770f6c https://git.kernel.org/stable/c/8e5eb1d6e6a3d7bbea9c92132d0cda5793176426 https://git.kernel.org/stable/c/be2d32f0c3fe333d14c0a9ca90328dacbc3e06b8 https://git.kernel.org/stable/c/c6da4fed7537aec19880c24f6c3a95065adb1406

CVSS v3.1

Source Entity [email protected]

Severity HIGH

7.8

Attack Vector

LOCAL

Complexity

LOW

Privileges

N/A

Interaction

NONE

Confidentiality

N/A

Integrity

N/A

Availability

N/A

Scope

UNCHANGED

RAW VECTOR CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2026-31720 Exploits & PoCs (Proof Of Concept)

GitHub https://github.com/foxirain/linux-kernel-codex-harness

View Code

May 06, 2026 MODIFIED

Vulnerability data updated via NVD.

Attack Vector Matrix

Access Vector LOCAL

Complexity LOW

Privileges N/A

Interaction NONE

CVSS Vector String


                                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected Stack

No specific products linked.