Bug 1793929 (CVE-2019-20396)

Summary:	CVE-2019-20396 libyang: heap-based buffer over-read in function lys_type_free() due to malformed pattern
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-r1	Doc Type:	If docs needed, set a value
Doc Text:	A heap-based buffer over-read flaw occurs in libyang in function lys_type_free() due to a malformed pattern statement value. Applications that use libyang to process untrusted input yang files may be vulnerable to this flaw, possibly causing a crash or information leaks.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2021-10-28 10:10:30 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:	1797550, 1797618, 1910046
Bug Blocks:	1790579

Description Riccardo Schirone 2020-01-22 09:53:18 UTC

A heap-based buffer over-read is present in libyang up to version v1.0-r1 in function lys_type_free() due to malformed pattern statement value. Applications that use libyang to parse untrusted input yang files may be vulnerable to this flaw, which would cause a crash or information leaks. 

Upstream issue:
https://github.com/CESNET/libyang/issues/740

Upstream fix:
https://github.com/CESNET/libyang/commit/a1f17693904ed6fecc8902c747fc50a8f20e6af8

Comment 1 Riccardo Schirone 2020-02-03 11:47:36 UTC

Created libyang tracking bugs for this issue:

Affects: fedora-all [bug 1797550]