---
id: CVE-2026-90018
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  staging: rtl8723bs: fix OOB read / stack overflow in rtw_get_wps_attr()

  rtw_get_wps_attr() walks WPS attributes inside a WPS IE taken from
  a wireless management frame.…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  staging: rtl8723bs: fix OOB read / stack overflow in rtw_get_wps_attr()

  rtw_get_wps_attr() walks WPS attributes inside a WPS IE taken from
  a wireless management frame.…
severity: high
cvss: 8.8
cvssVector: 'CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 554c0a3abf216c991c5ebddcdb2c08689ecd290b <
    931640dfcb8cfa08f6cfb46229716d8072356420
  - >-
    Linux >= 554c0a3abf216c991c5ebddcdb2c08689ecd290b <
    3a6457ebf39080b87c712657fdb38f34a24fc3ff
  - >-
    Linux >= 554c0a3abf216c991c5ebddcdb2c08689ecd290b <
    fd5e24ea8373347d0352f153a66e8647337d1b10
  - >-
    Linux >= 554c0a3abf216c991c5ebddcdb2c08689ecd290b <
    a53d1ac9ce63db07943b2b2248111003851fb00f
  - >-
    Linux >= 554c0a3abf216c991c5ebddcdb2c08689ecd290b <
    ff61aa3289355dafa811550a1764691cd1f5d33b
  - >-
    Linux >= 554c0a3abf216c991c5ebddcdb2c08689ecd290b <
    34f51d196c43a42046d229de5e79025d5ca553ca
  - >-
    Linux >= 554c0a3abf216c991c5ebddcdb2c08689ecd290b <
    99aa998dec83ba180822f70e6d48a514fc81c20d
  - Linux 4.12
published: '2026-09-16'
updated: '2026-09-16'
sourceUpdated: '2026-09-16T15:18:25.503'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-90018'
references:
  - url: 'https://git.kernel.org/stable/c/34f51d196c43a42046d229de5e79025d5ca553ca'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/3a6457ebf39080b87c712657fdb38f34a24fc3ff'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/931640dfcb8cfa08f6cfb46229716d8072356420'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/99aa998dec83ba180822f70e6d48a514fc81c20d'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/a53d1ac9ce63db07943b2b2248111003851fb00f'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/fd5e24ea8373347d0352f153a66e8647337d1b10'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/ff61aa3289355dafa811550a1764691cd1f5d33b'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-16T10:53:53.939Z'
epss: 0.0052
epssPercentile: 0.41663
---

## Overview

In the Linux kernel, the following vulnerability has been resolved:

staging: rtl8723bs: fix OOB read / stack overflow in rtw_get_wps_attr()

rtw_get_wps_attr() walks WPS attributes inside a WPS IE taken from
a wireless management frame. For each candidate attribute it only
checks that the fixed 4-byte attribute header (2-byte ID + 2-byte
length) fits inside the IE:

	if (attr_ptr + 4 > wps_ie + wps_ielen)
		break;
	u16 attr_id = get_unaligned_be16(attr_ptr);
	u16 attr_data_len = get_unaligned_be16(attr_ptr + 2);
	u16 attr_len = attr_data_len + 4;

attr_data_len (and therefore attr_len) is read directly from the
wire and is never checked against the remaining bytes in the IE
before being used as the size of:

	memcpy(buf_attr, attr_ptr, attr_len);

Since attr_len is fully attacker controlled (0 to 65535+4), this is
both a heap OOB read of wps_ie, and, more seriously, a stack buffer
overflow at several call sites where buf_attr is a single-byte
stack variable, e.g. rtw_get_wps_attr_content()'s callers passing
WPS_ATTR_SELECTED_REGISTRAR into a stack "u8 sr"/"u8
selected_registrar" (drivers/staging/rtl8723bs/os_dep/ioctl_cfg80211.c,
drivers/staging/rtl8723bs/core/rtw_mlme_ext.c). A crafted WPS IE in a
beacon or probe response processed during scanning can therefore
smash the stack of the parsing thread.

rtw_get_wps_attr_content() itself has no independent length check
and simply trusts the attr_len it gets back from rtw_get_wps_attr(),
so fixing the bound here also fixes that caller.

The "attr_ptr + 4 > wps_ie + wps_ielen" header check above was added
by commit 1463ca3ec6601 ("staging: rtl8723bs: fix OOB reads in
rtw_get_sec_ie(), rtw_get_wapi_ie(), and rtw_get_wps_attr()"), which
bounded the fixed header but never extended the check to cover the
variable-length attribute data that follows it. Add that missing
check before attr_len is used as a memcpy() length or accepted as a
match.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.