CVE-2026-64536: staging: rtl8723bs: fix OOB reads in is_ap_in_tkip() IE loop

Greg Kroah-Hartman <[email protected]> Mon, 27 Jul 2026 08:35:58 +0200
Newsgroups org.kernel.vger.linux-cve-announce
Message-ID <2026072757-CVE-2026-64536-3376@gregkh>
From: Greg Kroah-Hartman <[email protected]>

Description
===========

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

staging: rtl8723bs: fix OOB reads in is_ap_in_tkip() IE loop

The loop in is_ap_in_tkip() iterates over IEs without verifying that
enough bytes remain before dereferencing the IE header or its payload:

- pIE->element_id and pIE->length are read without checking that
  i + sizeof(*pIE) <= ie_length, so a truncated IE at the end of the
  buffer causes an OOB read.

- For WLAN_EID_VENDOR_SPECIFIC the code compares pIE->data + 12,
  which requires pIE->length >= 16.  For WLAN_EID_RSN it compares
  pIE->data + 8, requiring pIE->length >= 12.  Neither requirement
  is checked.

Add the missing IE header and payload bounds checks and guard each
data access with an explicit pIE->length minimum, matching the
pattern established in update_beacon_info().

The Linux kernel CVE team has assigned CVE-2026-64536 to this issue.


Affected and fixed versions
===========================

	Issue introduced in 4.12 with commit 554c0a3abf216c991c5ebddcdb2c08689ecd290b and fixed in 5.15.212 with commit ea3809f7e20bdff282b8cc1e94937d5fb9fb32c7
	Issue introduced in 4.12 with commit 554c0a3abf216c991c5ebddcdb2c08689ecd290b and fixed in 6.1.178 with commit d2055332297e24c63fffda943ef7a5eefc0a6019
	Issue introduced in 4.12 with commit 554c0a3abf216c991c5ebddcdb2c08689ecd290b and fixed in 6.6.145 with commit 6f26cc55affd9d7f88ae2f5d12db4ecf9072c209
	Issue introduced in 4.12 with commit 554c0a3abf216c991c5ebddcdb2c08689ecd290b and fixed in 6.12.96 with commit 204b22c8df115370037248859bf0fa62db73a396
	Issue introduced in 4.12 with commit 554c0a3abf216c991c5ebddcdb2c08689ecd290b and fixed in 6.18.39 with commit a6105ea8ca6ebbc04beaf3bcbf7dbb5985f5d395
	Issue introduced in 4.12 with commit 554c0a3abf216c991c5ebddcdb2c08689ecd290b and fixed in 7.1.4 with commit 4380b3860d887a13555ff024a58dfc05b490dfd6
	Issue introduced in 4.12 with commit 554c0a3abf216c991c5ebddcdb2c08689ecd290b and fixed in 7.2-rc3 with commit 3bf39f711ff27c64be8680a8938bcc5001982e81

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2026-64536
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	drivers/staging/rtl8723bs/core/rtw_wlan_util.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/ea3809f7e20bdff282b8cc1e94937d5fb9fb32c7
	https://git.kernel.org/stable/c/d2055332297e24c63fffda943ef7a5eefc0a6019
	https://git.kernel.org/stable/c/6f26cc55affd9d7f88ae2f5d12db4ecf9072c209
	https://git.kernel.org/stable/c/204b22c8df115370037248859bf0fa62db73a396
	https://git.kernel.org/stable/c/a6105ea8ca6ebbc04beaf3bcbf7dbb5985f5d395
	https://git.kernel.org/stable/c/4380b3860d887a13555ff024a58dfc05b490dfd6
	https://git.kernel.org/stable/c/3bf39f711ff27c64be8680a8938bcc5001982e81