Bug 1824157 (CVE-2020-11647)

Summary: CVE-2020-11647 wireshark: BACapp dissector crash (wnpa-sec-2020-07)
Product: [Other] Security Response Reporter: Guilherme de Almeida Suckevicz <gsuckevi>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED WONTFIX QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: denis, huzaifas, lemenkov, mruprich, msehnout, peter, rvokal, sergey.avseyev
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: wireshark 2.6.16, wireshark 3.0.10, wireshark 3.2.3 Doc Type: No Doc Update
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2021-06-29 20:29:40 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: 1824158, 1825011    
Bug Blocks: 1824159    

Description Guilherme de Almeida Suckevicz 2020-04-15 13:09:14 UTC 
In Wireshark 3.2.0 to 3.2.2, 3.0.0 to 3.0.9, and 2.6.0 to 2.6.15, the BACapp dissector could crash. This was addressed in epan/dissectors/packet-bacapp.c by limiting the amount of recursion.

References:
https://www.wireshark.org/security/wnpa-sec-2020-07.html
https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=16474

Upstream commit:
https://code.wireshark.org/review/gitweb?p=wireshark.git;a=commit;h=6f56fc9496db158218243ea87e3660c874a0bab0
Comment 1 Guilherme de Almeida Suckevicz 2020-04-15 13:09:31 UTC 
Created wireshark tracking bugs for this issue:

Affects: fedora-all [bug 1824158]
Comment 3 Todd Cullum 2020-04-16 20:30:54 UTC 
Statement:

The versions of Wireshark as shipped with Red Hat Enterprise Linux 7 and earlier are not affected by this issue because the commit was introduced in later versions.
Comment 4 Todd Cullum 2020-04-16 20:38:48 UTC 
External References:

https://www.wireshark.org/security/wnpa-sec-2020-07.html
Comment 6 Todd Cullum 2020-04-17 19:23:08 UTC 
This flaw appears to be caused because the fAbstractSyntaxNType() function in epan/dissectors/packet-bacapp.c calls other functions such as fLogRecord(), fLogMultipleRecord(), fEventParameter(), which in turn call fAbstractSyntaxNType(). A malformed packet could create a condition in which the recursion depth would overflow the stack size because there was no limitation on recursion depth.