CVE-2020-17525 : What You Need to Know

Subversion's mod_authz_svn module vulnerability can lead to a denial-of-service condition for users. Learn about the impact, technical details, and mitigation steps.

Understanding CVE-2020-17525

Subversion's mod_authz_svn vulnerability can cause server crashes, affecting service availability.

What is CVE-2020-17525?

The vulnerability in Subversion's mod_authz_svn module triggers a server crash when in-repository authz rules are used with specific configurations, impacting service availability.

The Impact of CVE-2020-17525

The vulnerability can lead to a denial-of-service condition, disrupting service for users accessing non-existing repository URLs.

Technical Details of CVE-2020-17525

Explore the specifics of the vulnerability to understand its implications.

Vulnerability Description

The flaw in mod_authz_svn causes server crashes when in-repository authz rules with specific options are used, affecting service availability.

Affected Systems and Versions

Product: Apache Subversion
Vendor: Apache Software Foundation
Affected Versions:
mod_authz_svn 1.10.7 (unaffected)
mod_authz_svn less than 1.14.1 (affected)

Exploitation Mechanism

The vulnerability is triggered when a client requests a non-existing repository URL, leading to a crash in the mod_authz_svn module.

Mitigation and Prevention

Discover the steps to mitigate the CVE-2020-17525 vulnerability.

Immediate Steps to Take

Avoid using in-repository authz rules files with the AuthzSVNReposRelativeAccessFile option.
Switch to an alternative configuration fetching authz rules from the server's filesystem.

Long-Term Security Practices

Regularly update Subversion to the latest version to patch known vulnerabilities.
Implement network security measures to prevent unauthorized access to the server.

Patching and Updates

Ensure timely installation of security updates and patches provided by Apache Software Foundation to address the vulnerability.