Vulnerability Name:

CVE-2018-5121 (CCN-138166)

Assigned:2018-01-23
Published:2018-01-23
Updated:2018-06-25
Summary:Low descenders on some Tibetan characters in several fonts on OS X are clipped when rendered in the addressbar. When used as part of an Internationalized Domain Name (IDN) this can be used for domain name spoofing attacks.
Note: This attack only affects OS X operating systems. Other operating systems are unaffected. This vulnerability affects Firefox < 58.
CVSS v3 Severity:5.3 Medium (CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N)
4.6 Medium (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/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): Low
Availibility (A): None
6.5 Medium (CCN CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N)
5.7 Medium (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/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): Required
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): None
Integrity (I): High
Availibility (A): None
CVSS v2 Severity:5.0 Medium (CVSS v2 Vector: AV:N/AC:L/Au:N/C:N/I:P/A:N)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Authentication (Au): None
Impact Metrics:Confidentiality (C): None
Integrity (I): Partial
Availibility (A): None
6.8 Medium (CCN CVSS v2 Vector: AV:N/AC:L/Au:S/C:N/I:C/A:N)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Athentication (Au): Single_Instance
Impact Metrics:Confidentiality (C): None
Integrity (I): Complete
Availibility (A): None
Vulnerability Type:CWE-20
Vulnerability Consequences:Bypass Security
References:Source: MITRE
Type: CNA
CVE-2018-5121

Source: BID
Type: Third Party Advisory, VDB Entry
102786

Source: CCN
Type: BID-102786
Mozilla Firefox MFSA2018-02 Multiple Security Vulnerabilities

Source: SECTRACK
Type: Third Party Advisory, VDB Entry
1040270

Source: CONFIRM
Type: Issue Tracking, Permissions Required
https://bugzilla.mozilla.org/show_bug.cgi?id=1402368

Source: XF
Type: UNKNOWN
firefox-cve20185121-sec-bypass(138166)

Source: CCN
Type: Mozilla Foundation Security Advisory 2018-02
Security vulnerabilities fixed in Firefox 58

Source: CONFIRM
Type: Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2018-02/

Vulnerable Configuration:Configuration 1:
  • cpe:/a:mozilla:firefox:*:*:*:*:*:*:*:* (Version <= 57.0.4)
  • AND
  • cpe:/o:apple:mac_os_x:*:*:*:*:*:*:*:*

    • * Denotes that component is vulnerable
    Oval Definitions
    Definition IDClassTitleLast Modified
    oval:org.opensuse.security:def:20185121
    V
    		CVE-2018-5121
    2022-06-30
    oval:org.opensuse.security:def:111899
    P
    		MozillaFirefox-92.0-1.2 on GA media (Moderate)
    2022-01-17
    oval:org.opensuse.security:def:105476
    P
    		MozillaFirefox-92.0-1.2 on GA media (Moderate)
    2021-10-01
    oval:com.ubuntu.artful:def:20185121000
    V
    		CVE-2018-5121 on Ubuntu 17.10 (artful) - low.
    2018-06-11
    oval:com.ubuntu.xenial:def:201851210000000
    V
    		CVE-2018-5121 on Ubuntu 16.04 LTS (xenial) - low.
    2018-06-11
    oval:com.ubuntu.trusty:def:20185121000
    V
    		CVE-2018-5121 on Ubuntu 14.04 LTS (trusty) - low.
    2018-06-11
    oval:com.ubuntu.xenial:def:20185121000
    V
    		CVE-2018-5121 on Ubuntu 16.04 LTS (xenial) - low.
    2018-06-11
    BACK
    mozilla firefox *
    apple mac os x *