Bug 1468498 (CVE-2017-10982)

Summary: CVE-2017-10982 freeradius: Out-of-bounds read in fr_dhcp_decode_options()
Product: [Other] Security Response Reporter: Adam Mariš <amaris>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED ERRATA QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: dpal, jdennis, lemenkov, nikolai.kondrashov, pkis, security-response-team
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: freeradius 2.2.10 Doc Type: If docs needed, set a value
Doc Text:
An out-of-bounds read flaw was found in the way FreeRADIUS server handles decoding of DHCP packets. A remote attacker could use this flaw to crash the FreeRADIUS server by sending a specially crafted DHCP request.
Story Points: ---
Clone Of: Environment:
Last Closed: 2017-08-02 09:39:35 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: 1469124, 1469125, 1471858    
Bug Blocks: 1468570    
Attachments:
Description Flags
Proposed patch none

Description Adam Mariš 2017-07-07 09:10:17 UTC
The fr_dhcp_decode_options() function does not do proper bounds checks on option lengths, leading to out-of-bounds read.

The server can read up to 253 octets more data than it should. Depending on memory layout, this read may initiate a page fault, and cause the server to crash. 

The security impact is denial of service by any network device capable of sending DHCP packets to FreeRADIUS, which sends packets with malformed options.

Affected versions: 2.0.0 through 2.2.9, inclusive.

Comment 1 Adam Mariš 2017-07-07 09:10:25 UTC
Acknowledgments:

Name: the FreeRADIUS project
Upstream: Guido Vranken

Comment 2 Adam Mariš 2017-07-07 12:12:19 UTC
Created attachment 1295277 [details]
Proposed patch

Comment 6 Dhiru Kholia 2017-07-17 14:34:49 UTC
Created freeradius tracking bugs for this issue:

Affects: fedora-all [bug 1471858]

Comment 7 errata-xmlrpc 2017-07-18 03:42:20 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 6

Via RHSA-2017:1759 https://access.redhat.com/errata/RHSA-2017:1759

Comment 8 Dhiru Kholia 2017-08-02 09:44:20 UTC
External References:

http://freeradius.org/security/fuzzer-2017.html