Debian update for subversion

1) NULL pointer dereference

EUVDB-ID: #VU50623

Risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

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 subversion package to version 1.10.4-1+deb10u2.

Vulnerable software versions

subversion (Debian package): 1.10.0-1 - 1.10.6-1+b1

External links

http://www.debian.org/security/2021/dsa-4851

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.