Bug 1793924 (CVE-2019-20395)

Summary:	CVE-2019-20395 libyang: stack-overflow when parsing yang files with self-referential union types
Product:	[Other] Security Response	Reporter:	Riccardo Schirone <rschiron>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	CC:	mruprich, tkorbar
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	libyang 1.0-r1	Doc Type:	If docs needed, set a value
Doc Text:	A stack-overflow flaw was found in libyang due to a self-referential union type containing leafrefs. Applications that use libyang to process untrusted input YANG files may crash while processing malformed files.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2021-10-28 10:10:23 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:	1797548, 1797616, 1910046
Bug Blocks:	1790579

Description Riccardo Schirone 2020-01-22 09:33:35 UTC

A stack-overflow is present in libyang up to version v1.0-r1 due to self-referential union type containing leafrefs. Applications that use libyang to parse untrusted input yang files may crash.

Upstream issue:
https://github.com/CESNET/libyang/issues/724

Upstream fix:
https://github.com/CESNET/libyang/commit/4e610ccd87a2ba9413819777d508f71163fcc237

Comment 1 Riccardo Schirone 2020-02-03 11:45:16 UTC

Created libyang tracking bugs for this issue:

Affects: fedora-all [bug 1797548]