#VU50623 NULL pointer dereference in Subversion - CVE-2020-17525

Vulnerability identifier: #VU50623

Vulnerability risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2020-17525

CWE-ID: CWE-476

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Subversion
Server applications / Frameworks for developing and running applications

Vendor: Apache Foundation

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference  when the Subversion is configured to use in-repository authz rules with the AuthzSVNReposRelativeAccessFile option. A remote non-authenticated attacker can send specially crafted request to a non-existing URL, trigger a NULL pointer dereference in the mod_authz_svn module and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Subversion: 1.9.0 rc1 - 1.9.12, 1.10.0 alpha1 - 1.14.0

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

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.