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CVE-2018-9127: Botan Project: Improper Certificate Validation
CVE-2018-9127 is rated critical with a CVSS v3.0 base score of 9.8 and affects Botan Project. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available.
Vulnerability description
Botan 2.2.0 - 2.4.0 (fixed in 2.5.0) improperly handled wildcard certificates and could accept 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.
Severity breakdown
CVSS v3.0 9.8: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
- Attack complexity: Low. No special conditions; the attack can be repeated reliably.
- Privileges required: None. No account or prior access is needed.
- User interaction: None. No action from any user is needed.
- Scope: Unchanged. Impact stays within the vulnerable component.
- Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
- Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
- Availability impact: High. Total loss of availability; the component can be shut down.
Underlying weakness
CWE-295: Improper Certificate Validation
The product does not validate, or incorrectly validates, a certificate.
Affected products
- Botan Project: from 2.2.0 up to and including 2.4.0