Ubuntu update for subversion

1) NULL pointer dereference

EUVDB-ID: #VU50623

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 - NULL Pointer Dereference

Exploit availability: No

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

Update the affected package subversion to the latest version.

Vulnerable software versions

Ubuntu: 16.04

libsvn1 (Ubuntu package): before UA Infra or UA Desktop

subversion (Ubuntu package): before UA Infra or UA Desktop

libapache2-mod-svn (Ubuntu package): before UA Infra or UA Desktop

libapache2-svn (Ubuntu package): before UA Infra or UA Desktop

CPE2.3

• cpe:2.3:o:canonical:ubuntu:16.04:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:libsvn1_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:o:canonical:subversion_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:o:canonical:libapache2-mod-svn_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:o:canonical:libapache2-svn_ubuntu_package:*:*:*:*:*:ubuntu:*:*

External links

https://ubuntu.com/security/notices/USN-5322-1

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.