CVE-2021-23986

medium
New! CVE Severity Now Using CVSS v3

The calculated severity for CVEs has been updated to use CVSS v3 by default. CVEs that do not have a CVSS v3 score will fall back CVSS v2 for calculating severity. Severity display preferences can be toggled in the settings dropdown.

Description

A malicious extension with the 'search' permission could have installed a new search engine whose favicon referenced a cross-origin URL. The response to this cross-origin request could have been read by the extension, allowing a same-origin policy bypass by the extension, which should not have cross-origin permissions. This cross-origin request was made without cookies, so the sensitive information disclosed by the violation was limited to local-network resources or resources that perform IP-based authentication. This vulnerability affects Firefox < 87.

References

https://www.mozilla.org/security/advisories/mfsa2021-10/

https://bugzilla.mozilla.org/show_bug.cgi?id=1692623

Details

Source: MITRE

Published: 2021-03-31

Updated: 2021-08-06

Type: CWE-346

Risk Information

CVSS v2

Base Score: 4.3

Vector: AV:N/AC:M/Au:N/C:P/I:N/A:N

Impact Score: 2.9

Exploitability Score: 8.6

Severity: MEDIUM

CVSS v3

Base Score: 6.5

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

Impact Score: 3.6

Exploitability Score: 2.8

Severity: MEDIUM

Vulnerable Software

Configuration 1

OR

cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*

Tenable Plugins

View all (4 total)

IDNameProductFamilySeverity
149233GLSA-202104-10 : Mozilla Firefox: Multiple vulnerabilitiesNessusGentoo Local Security Checks
high
148135Ubuntu 16.04 LTS / 18.04 LTS / 20.04 LTS / 20.10 : Firefox vulnerabilities (USN-4893-1)NessusUbuntu Local Security Checks
high
148015Mozilla Firefox < 87.0NessusMacOS X Local Security Checks
high
148014Mozilla Firefox < 87.0NessusWindows
high