Bug 346341 (CVE-2007-4997)

Summary:	CVE-2007-4997 kernel ieee80211 off-by-two integer underflow
Product:	[Other] Security Response	Reporter:	Mark J. Cox <mjc>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	gnichols, jkeck, kernel-maint, kernel-mgr, kreilly, rt-maint
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
URL:	http://nvd.nist.gov/nvd.cfm?cvename=CVE-2007-4997
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2015-08-24 15:38:37 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:	346361, 346381, 346391, 346401
Bug Blocks:

Description Mark J. Cox 2007-10-23 07:43:24 UTC

Common Vulnerabilities and Exposures assigned an identifier CVE-2007-4997 to the following vulnerability:

** RESERVED ** This candidate has been reserved by an organization or individual that will use it when announcing a new security problem.  When the candidate has been publicized, the details for this candidate will be provided.

References:

Comment 1 Mark J. Cox 2007-10-23 07:45:05 UTC

Chris Evans discovered that a malicious 80211 frame can crash machine if certain
drivers, chipsets, and firmware is in use.  

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=04045f98e0457aba7d4e6736f37eed189c48a5f7

eported by Chris Evans <scarybeasts>:

> The summary is that an evil 80211 frame can crash out a victim's
> machine. It only applies to drivers using the 80211 wireless code, and
> only then to certain drivers (and even then depends on a card's
> firmware not dropping a dubious packet). I must confess I'm not
> keeping track of Linux wireless support, and the different protocol
> stacks etc.
>
> Details are as follows:
>
> ieee80211_rx() does not explicitly check that "skb->len >= hdrlen".
> There are other skb->len checks, but not enough to prevent a subtle
> off-by-two error if the frame has the IEEE80211_STYPE_QOS_DATA flag
> set.
>
> This leads to integer underflow and crash here:
>
> if (frag != 0)
>    flen -= hdrlen;
>
> (flen is subsequently used as a memcpy length parameter).

Acknowledgements:

Red Hat would like to credit Chris Evans for reporting this issue.

Comment 3 Jonathan Larmour 2007-10-23 09:06:07 UTC

I should not be on this bug.

Comment 4 Mark J. Cox 2007-11-08 18:19:09 UTC

Now also public at http://scary.beasts.org/security/CESA-2007-007.html