Bug 1922303 (CVE-2020-17525)

Summary:	CVE-2020-17525 subversion: Remote unauthenticated denial of service in mod_authz_svn
Product:	[Other] Security Response	Reporter:	Pedro Sampaio <psampaio>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	icesalov, jorton, security-response-team, vanmeeuwen+fedora
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	subversion 1.14.1, subversion 1.10.7	Doc Type:	If docs needed, set a value
Doc Text:	A null-pointer-dereference flaw was found in mod_authz_svn of subversion. This flaw allows a remote, unauthenticated attacker to cause a denial of service in some server configurations. The highest threat from this vulnerability is to system availability.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2021-02-15 10:09:43 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:	1923920, 1923921, 1923922, 1923923, 1923924, 1923925, 1923926, 1923927, 1923928, 1927472
Bug Blocks:	1922304

Description Pedro Sampaio 2021-01-29 15:44:46 UTC

A flaw was found in subversion versions 1.9.0 through 1.10.6 and 1.11.0 through 1.14.0. Subversion's mod_authz_svn module will crash if the server is using in-repository authz rules with the AuthzSVNReposRelativeAccessFile option and a client sends a request for a non-existing repository URL. This can lead to disruption for users of the service.

Comment 1 Pedro Sampaio 2021-01-29 15:44:49 UTC

Acknowledgments:

Name: the  Subversion security team
Upstream: Thomas Åkesson (simonsoft.se)

Comment 8 Huzaifa S. Sidhpurwala 2021-02-02 10:22:54 UTC

Mitigation:

As per upstream "As a workaround, the use of in-repository authz rules files with the AuthzSVNReposRelativeAccessFile can be avoided by switching  to an alternative configuration which fetches an authz rules file from the server's filesystem, rather than from an SVN repository."

Comment 10 Guilherme de Almeida Suckevicz 2021-02-10 20:08:09 UTC

Created subversion tracking bugs for this issue:

Affects: fedora-all [bug 1927472]

Comment 11 Huzaifa S. Sidhpurwala 2021-02-11 03:35:16 UTC

External References:

https://subversion.apache.org/security/CVE-2020-17525-advisory.txt

Comment 12 errata-xmlrpc 2021-02-15 07:31:00 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.1 Extended Update Support

Via RHSA-2021:0509 https://access.redhat.com/errata/RHSA-2021:0509

Comment 13 errata-xmlrpc 2021-02-15 07:32:45 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2021:0507 https://access.redhat.com/errata/RHSA-2021:0507

Comment 14 errata-xmlrpc 2021-02-15 07:40:09 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.2 Extended Update Support

Via RHSA-2021:0508 https://access.redhat.com/errata/RHSA-2021:0508

Comment 15 Product Security DevOps Team 2021-02-15 10:09:43 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-2020-17525