The lifecycle of IPC Actors allows managed actors to outlive their manager actors; and the former must ensure that they are not attempting to use a dead actor they have a reference to. Such a check was omitted in WebGL, resulting in a use-after-free and a potentially exploitable crash. This vulnerability affects Firefox < 84.

The remote Ubuntu 16.04 LTS / 18.04 LTS / 20.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-4671-1 advisory.

    Multiple security issues were discovered in Firefox. If a user were tricked into opening a specially     crafted website, an attacker could potentially exploit these to cause a denial of service, obtain     sensitive information, bypass the CSS sanitizer, bypass security restrictions, spoof the URL bar, or     execute arbitrary code. (CVE-2020-16042, CVE-2020-26971, CVE-2020-26972, CVE-2020-26793, CVE-2020-26974,     CVE-2020-26976, CVE-2020-26978, CVE-2020-26979, CVE-2020-35113, CVE-2020-35114)

    It was discovered that the proxy.onRequest API did not catch view-source URLs. If a user were tricked in     to installing an extension with the proxy permission and opening View Source, an attacker could     potentially exploit this to obtain sensitive information. (CVE-2020-35111)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The version of Firefox installed on the remote macOS or Mac OS X host is prior to 84.0. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2020-54 advisory. Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The version of Firefox installed on the remote Windows host is prior to 84.0. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2020-54 advisory. Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Severity
144299	Ubuntu 16.04 LTS / 18.04 LTS / 20.04 LTS : Firefox vulnerabilities (USN-4671-1)	Nessus	Ubuntu Local Security Checks	critical
144283	Mozilla Firefox < 84.0	Nessus	MacOS X Local Security Checks	critical
144282	Mozilla Firefox < 84.0	Nessus	Windows	critical

Detections

Analytics

CVE-2020-26972

critical

Tenable Plugins

critical

critical

critical