Vulnerability Name:

CVE-2020-26967 (CCN-191937)

Assigned:2020-11-17
Published:2020-11-17
Updated:2020-12-10
Summary:When listening for page changes with a Mutation Observer, a malicious web page could confuse Firefox Screenshots into interacting with elements other than those that it injected into the page. This would lead to internal errors and unexpected behavior in the Screenshots code. This vulnerability affects Firefox < 83.
CVSS v3 Severity:6.5 Medium (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 (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
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:4.3 Medium (CVSS v2 Vector: AV:N/AC:M/Au:N/C:N/I:P/A:N)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Medium
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-noinfo
Vulnerability Consequences:Bypass Security
References:Source: MITRE
Type: CNA
CVE-2020-26967

Source: MISC
Type: Issue Tracking, Permissions Required, Vendor Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1665820

Source: XF
Type: UNKNOWN
firefox-cve202026967-sec-bypass(191937)

Source: CCN
Type: Mozilla Foundation Security Advisory 2020-50
Security Vulnerabilities fixed in Firefox 83

Source: CONFIRM
Type: Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2020-50/

Vulnerable Configuration:Configuration 1:
  • cpe:/a:mozilla:firefox:*:*:*:*:*:*:*:* (Version < 83.0)

    • * Denotes that component is vulnerable
    Oval Definitions
    Definition IDClassTitleLast Modified
    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
    BACK
    mozilla firefox *