Vulnerability Name:

CVE-2018-21246 (CCN-185777)

Assigned:2020-06-15
Published:2020-06-15
Updated:2020-06-26
Summary:Caddy before 0.10.13 mishandles TLS client authentication, as demonstrated by an authentication bypass caused by the lack of the StrictHostMatching mode.
CVSS v3 Severity:9.8 Critical (CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)
8.5 High (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): High
Integrity (I): High
Availibility (A): High
7.5 High (CCN CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N)
6.5 Medium (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): None
Integrity (I): High
Availibility (A): None
CVSS v2 Severity:7.5 High (CVSS v2 Vector: AV:N/AC:L/Au:N/C:P/I:P/A:P)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Authentication (Au): None
Impact Metrics:Confidentiality (C): Partial
Integrity (I): Partial
Availibility (A): Partial
7.8 High (CCN CVSS v2 Vector: AV:N/AC:L/Au:N/C:N/I:C/A:N)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Athentication (Au): None
Impact Metrics:Confidentiality (C): None
Integrity (I): Complete
Availibility (A): None
Vulnerability Type:CWE-287
Vulnerability Consequences:Bypass Security
References:Source: MITRE
Type: CNA
CVE-2018-21246

Source: CCN
Type: Gentoo's Bugzilla - Bug 715214
(CVE-2018-21246) - www-servers/caddy: Possible TLS client auth bypass (CVE-2018-21246)

Source: XF
Type: UNKNOWN
caddy-cve201821246-sec-bypass(185777)

Source: CCN
Type: Caddy GIT Repository
httpserver: Prevent TLS client authentication bypass in 3 ways #2099

Vulnerable Configuration:Configuration CCN 1:
  • cpe:/a:caddyserver:caddy:0.10.12:*:*:*:*:*:*:*

    • * Denotes that component is vulnerable
    BACK
    caddyserver caddy 0.10.12