Bug 2044451 (CVE-2021-45960)

Summary:	CVE-2021-45960 expat: Large number of prefixed XML attributes on a single tag can crash libexpat
Product:	[Other] Security Response	Reporter:	Pedro Sampaio <psampaio>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	abrt-devel-list, bdettelb, caswilli, cschalle, csutherl, erack, fhrdina, fjansen, gzaronik, jburrell, jclere, jhorak, jorton, jwong, jwon, kaycoth, krathod, micjohns, mturk, nobody, pjindal, psegedy, rcritten, sthirugn, stransky, szappis, tcarlin, tfister, tkasparek, tkorbar, tpopela, tsasak, vkrizan, vkumar, vmugicag
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	expat 2.4.3	Doc Type:	If docs needed, set a value
Doc Text:	expat (libexpat) is susceptible to a software flaw that causes process interruption. When processing a large number of prefixed XML attributes on a single tag can libexpat can terminate unexpectedly due to buffer overrun. The highest threat from this vulnerability is to availability.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2022-05-05 01:15:24 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:	2053208, 2044452, 2052232, 2052234, 2052235, 2052236, 2052237, 2052238, 2052239, 2058549, 2058550, 2058551, 2058552, 2058553, 2058554, 2060192, 2060197, 2060199, 2060203, 2060208, 2060210
Bug Blocks:	2044492

Description Pedro Sampaio 2022-01-24 16:25:40 UTC

In Expat (aka libexpat) before 2.4.3, a left shift by 29 (or more) places in the storeAtts function in xmlparse.c can lead to realloc misbehavior (e.g., allocating too few bytes, or only freeing memory). 

References:

https://github.com/libexpat/libexpat/issues/531
https://github.com/libexpat/libexpat/pull/534
https://bugzilla.mozilla.org/show_bug.cgi?id=1217609
http://www.openwall.com/lists/oss-security/2022/01/17/3

Comment 1 Pedro Sampaio 2022-01-24 16:26:02 UTC

Created expat tracking bugs for this issue:

Affects: fedora-all [bug 2044452]

Comment 12 errata-xmlrpc 2022-03-16 16:16:27 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2022:0951 https://access.redhat.com/errata/RHSA-2022:0951

Comment 13 errata-xmlrpc 2022-03-28 11:49:13 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2022:1069 https://access.redhat.com/errata/RHSA-2022:1069

Comment 14 Product Security DevOps Team 2022-05-05 01:15:20 UTC

This bug is now closed. Further updates for individual products will be reflected on the CVE page(s):

https://access.redhat.com/security/cve/cve-2021-45960

Comment 15 errata-xmlrpc 2022-10-26 20:07:07 UTC

This issue has been addressed in the following products:

  Red Hat JBoss Core Services

Via RHSA-2022:7144 https://access.redhat.com/errata/RHSA-2022:7144

Comment 16 errata-xmlrpc 2022-10-26 20:20:37 UTC

This issue has been addressed in the following products:

  JBoss Core Services on RHEL 7
  JBoss Core Services for RHEL 8

Via RHSA-2022:7143 https://access.redhat.com/errata/RHSA-2022:7143