Bug 1978135 (CVE-2021-34813)

Summary:	CVE-2021-34813 libolm: allows a malicious Matrix homeserver to crash a client
Product:	[Other] Security Response	Reporter:	Dhananjay Arunesh <darunesh>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED NOTABUG	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	vitaly
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2021-10-28 05:30:14 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:	1978136
Bug Blocks:

Description Dhananjay Arunesh 2021-07-01 08:05:02 UTC

Matrix libolm before 3.2.3 allows a malicious Matrix homeserver to crash a client (while it is attempting to retrieve an Olm encrypted room key backup from the homeserver) because olm_pk_decrypt has a stack-based buffer overflow. Remote code execution might be possible for some nonstandard build configurations.

References:
https://gitlab.matrix.org/matrix-org/olm/-/releases/3.2.3
https://matrix.org/blog/2021/06/14/adventures-in-fuzzing-libolm
https://gitlab.matrix.org/matrix-org/olm/-/commit/ccc0d122ee1b4d5e5ca4ec1432086be17d5f901b

Comment 1 Dhananjay Arunesh 2021-07-01 08:05:26 UTC

Created libolm tracking bugs for this issue:

Affects: epel-8 [bug 1978136]