Improper Certificate Validation in Botan - CVE-2018-9127
Published: August 3, 2020
Vulnerability identifier: #VU33133
CSH Severity: Medium
CVSSv4.0: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2018-9127
CWE-ID: CWE-295
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
Botan
Botan
Software vendor:
Randombit
Randombit
Description
The vulnerability allows a remote attacker to bypass implemented security restrictions.
The vulnerability exists due to Botan 2.2.0 - 2.4.0 improperly handles wildcard certificates and accepts certain certificates as valid for hostnames when, under RFC 6125 rules, they should not match. This only affects certificates issued to the same domain as the host, so to impersonate a host one must already have a wildcard certificate matching other hosts in the same domain. For example, b*.example.com would match some hostnames that do not begin with a 'b' character.
Remediation
Install updates from vendor's website.