CVE-2020-17525

Public Exploit
Remote unauthenticated denial-of-service in Subversion mod_authz_svn

Description

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. This issue was fixed in mod_dav_svn+mod_authz_svn servers 1.14.1 and mod_dav_svn+mod_authz_svn servers 1.10.7

Remediation

Workaround:

  • 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.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 11.63% Top 10%
Vendor Advisory apache.org
Affected: Apache Software Foundation Apache Subversion
Published at:
Updated at:

References

Link Tags
https://subversion.apache.org/security/CVE-2020-17525-advisory.txt patch vendor advisory exploit
https://lists.debian.org/debian-lts-announce/2021/05/msg00000.html third party advisory mailing list

Frequently Asked Questions

What is the severity of CVE-2020-17525?
CVE-2020-17525 has been scored as a high severity vulnerability.
How to fix CVE-2020-17525?
As a workaround for remediating CVE-2020-17525: 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.
Is CVE-2020-17525 being actively exploited in the wild?
It is possible that CVE-2020-17525 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~12% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-17525?
CVE-2020-17525 affects Apache Software Foundation Apache Subversion.
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