CVE-2015-7826
Publication date 10 April 2017
Last updated 25 August 2025
Ubuntu priority
Description
botan 1.11.x before 1.11.22 improperly handles wildcard matching against hostnames, which might allow remote attackers to have unspecified impact via a valid X.509 certificate, as demonstrated by accepting *.example.com as a match for bar.foo.example.com. Otherwise valid certificates using wildcards would be accepted as matching certain hostnames that should they should not according to RFC 6125. For example a certificate issued for ‘*.example.com’ should match ‘foo.example.com’ but not ‘example.com’ or ‘bar.foo.example.com’. Previously Botan would accept such a certificate as valid for ‘bar.foo.example.com’. RFC 6125 also requires that when matching a X.509 certificate against a DNS name, the CN entry is only compared if no subjectAlternativeName entry is available. Previously X509_Certificate::matches_dns_name would always check both names.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| botan1.10 | ||
| 14.04 LTS trusty |
Not affected
|
|
Notes
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score |
9.8 · Critical
|
| Attack vector | Network |
| Attack complexity | Low |
| Privileges required | None |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | High |
| Integrity impact | High |
| Availability impact | High |
| Vector | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |