Bug 1384403 (CVE-2016-8658)

Summary:	CVE-2016-8658 kernel: Stack buffer overflow in brcmf_cfg80211_start_ap
Product:	[Other] Security Response	Reporter:	Andrej Nemec <anemec>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED WONTFIX	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	CC:	agordeev, aquini, arm-mgr, bhu, dhoward, esammons, fhrbata, gansalmon, iboverma, ichavero, itamar, jforbes, jkacur, joelsmith, jonathan, jross, jwboyer, kernel-maint, kernel-mgr, labbott, lgoncalv, lwang, madhu.chinakonda, matt, mchehab, mcressma, mguzik, nmurray, pholasek, plougher, rt-maint, rvrbovsk, slawomir, vdronov, williams
Target Milestone:	---	Keywords:	Reopened, Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:	Stack-based buffer overflow in the brcmf_cfg80211_start_ap() function in 'drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c' in the Linux kernel before 4.7.5 allows local users to cause a denial of service (system crash) or possibly have unspecified other impact via a long SSID Information Element in a command to a Netlink socket.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2016-10-19 15:47:59 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	1384405
Bug Blocks:	1384406

Description Andrej Nemec 2016-10-13 08:56:50 UTC

A stack based buffer overflow vulnerability was found in brcmf_cfg80211_start_ap() function. User-space can choose to omit NL80211_ATTR_SSID and only provide raw IE TLV data. When doing so it can provide SSID IE with length exceeding the allowed size. The driver further processes this IE copying it into a local variable without checking the length. Due to the nature of the flaw, privilege escalation cannot be fully ruled out, although we believe it is unlikely.

References:

http://seclists.org/oss-sec/2016/q4/111

Upstream patch:

https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=ded89912156b1a47d940a0c954c43afbabd0c42c

Comment 1 Andrej Nemec 2016-10-13 08:58:42 UTC

Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 1384405]

Comment 2 Justin M. Forbes 2016-10-13 15:20:05 UTC

This was fixed in stable 4.7.5 currently available in updates for all supported Fedora releases.

Comment 4 Vladis Dronov 2016-10-19 15:45:16 UTC

Statement:

This issue does not affect the Linux kernel packages as shipped with Red Hat Enterprise Linux 5, 6, as the code with the flaw is not present in the products listed.

This issue affects the Linux kernel packages as shipped with Red Hat Enterprise Linux 7 and Red Hat Enterprise MRG-2. This has been rated as having Low security impact and is not currently planned to be addressed in future updates. For additional information, refer to the Red Hat Enterprise Linux Life Cycle: https://access.redhat.com/support/policy/updates/errata/.