Bug 2027458 (CVE-2019-8921)

Summary:	CVE-2019-8921 bluez: information leak in service_attr_req() in sdpd-request.c via a crafted CSTATE
Product:	[Other] Security Response	Reporter:	Guilherme de Almeida Suckevicz <gsuckevi>
Component:	vulnerability	Assignee:	Nobody <nobody>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	bdettelb, bnocera, darcari, dwmw2, dzickus, hwkernel-mgr, spacewar
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	bluez 5.49	Doc Type:	If docs needed, set a value
Doc Text:	An issue was discovered in bluetoothd in BlueZ through version 5.48. The vulnerability lies in the handling of buffered data where it is possible to cause the server to return more bytes than the buffer actually holds, resulting in leaking arbitrary heap data.	Story Points:	---
Clone Of:		Environment:
Last Closed:		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:	2031790
Bug Blocks:	2027460

Description Guilherme de Almeida Suckevicz 2021-11-29 17:42:52 UTC

An issue was discovered in bluetoothd in BlueZ through 5.48. The vulnerability lies in the handling of a SVC_ATTR_REQ by the SDP implementation. By crafting a malicious CSTATE, it is possible to trick the server into returning more bytes than the buffer actually holds, resulting in leaking arbitrary heap data. The root cause can be found in the function service_attr_req of sdpd-request.c. The server does not check whether the CSTATE data is the same in consecutive requests, and instead simply trusts that it is the same.

Reference:
https://ssd-disclosure.com/ssd-advisory-linux-bluez-information-leak-and-heap-overflow/

Comment 1 Peter Robinson 2021-11-29 22:24:01 UTC

As per you note this was vulnerable "through 5.48". We build 5.49 for Fedora 27/28/29 on Mar 20 2018, this CVE has been fixed for nearly 4 years in Fedora why is this being opened now?

Comment 2 Peter Robinson 2021-11-29 22:32:09 UTC

Actually it looks like el8 is 5.56-2.el8 so it looks like this is fixed in RHEL-8 too

Comment 3 Guilherme de Almeida Suckevicz 2021-11-30 17:02:01 UTC

In reply to comment #1:
> As per you note this was vulnerable "through 5.48". We build 5.49 for Fedora
> 27/28/29 on Mar 20 2018, this CVE has been fixed for nearly 4 years in
> Fedora why is this being opened now?

Hi, this is a flaw bug and it's used to track all Red Hat products that may be affected by this issue, it's not just for Fedora.