Bug 1793932 (CVE-2019-20394)

Summary:	CVE-2019-20394 libyang: double-free in yyparse() when a type statement is used in a notification statement
Product:	[Other] Security Response	Reporter:	Riccardo Schirone <rschiron>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	mruprich, tkorbar
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	libyang 1.0-r3	Doc Type:	If docs needed, set a value
Doc Text:	A double-free flaw occurs in libyang in function yyparse() when a type statement is used in a notification statement. Applications that use libyang to process untrusted input YANG files may be vulnerable to this flaw, possibly causing a crash or potential code execution.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2021-10-28 10:10:36 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:	1797544, 1797620, 1910046
Bug Blocks:	1790579

Description Riccardo Schirone 2020-01-22 09:57:42 UTC

A double-free is present in libyang up to version v1.0-r3 in function yyparse() when a type statement in used in a notification statement. Applications that use libyang to parse untrusted input yang files may be vulnerable to this flaw, which would cause a crash or potentially code execution.

Upstream issue:
https://github.com/CESNET/libyang/issues/769

Upstream fix:
https://github.com/CESNET/libyang/commit/6cc51b1757dfbb7cff92de074ada65e8523289a6

Comment 1 Riccardo Schirone 2020-02-03 11:38:53 UTC

Created libyang tracking bugs for this issue:

Affects: fedora-all [bug 1797544]