Documents formed using data: URLs in an OBJECT element failed to inherit the CSP of the creating context. This allowed the execution of scripts that should have been blocked, albeit with a unique opaque origin. This vulnerability affects Firefox < 76.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - Documents formed using data: URLs in an OBJECT element failed to inherit the CSP of the creating context.
    This allowed the execution of scripts that should have been blocked, albeit with a unique opaque origin.
    This vulnerability affects Firefox < 76. (CVE-2020-12391)

Note that Nessus relies on the presence of the package as reported by the vendor.

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-4353-1 advisory.

    Multiple security issues were discovered in Firefox. If a user were tricked in to opening a specially     crafted website, an attacker could potentially exploit these to cause a denial of service, bypass security     restrictions, spoof the URL bar, or execute arbitrary code. (CVE-2020-6831, CVE-2020-12387,     CVE-2020-12390, CVE-2020-12391, CVE-2020-12394, CVE-2020-12395, CVE-2020-12396)

    It was discovered that the Devtools Copy as cURL feature did not properly escape the HTTP POST     data of a request. If a user were tricked in to using the Copy as cURL feature to copy and paste a     command with specially crafted data in to a terminal, an attacker could potentially exploit this to obtain     sensitive information from local files. (CVE-2020-12392)

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 Windows host is prior to 76.0. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2020-16 advisory.

  - A race condition when running shutdown code for Web     Worker led to a use-after-free vulnerability. This     resulted in a potentially exploitable crash.
    (CVE-2020-12387)

  - The Firefox content processes did not sufficiently     lockdown access control which could result in a sandbox     escape.Note: this issue only affects Firefox on     Windows operating systems. (CVE-2020-12388,     CVE-2020-12389)

  - A buffer overflow could occur when parsing and     validating SCTP chunks in WebRTC. This could have led to     memory corruption and a potentially exploitable crash.
    (CVE-2020-6831)

  - Incorrect origin serialization of URLs with IPv6     addresses could lead to incorrect security checks     (CVE-2020-12390)

  - Documents formed using data: URLs in an     object element failed to inherit the CSP of     the creating context. This allowed the execution of     scripts that should have been blocked, albeit with a     unique opaque origin. (CVE-2020-12391)

  - The 'Copy as cURL' feature of Devtools' network tab did     not properly escape the HTTP POST data of a request,     which can be controlled by the website. If a user used     the 'Copy as cURL' feature and pasted the command into a     terminal, it could have resulted in the disclosure of     local files. (CVE-2020-12392)

  - The 'Copy as cURL' feature of Devtools' network tab did     not properly escape the HTTP method of a request, which     can be controlled by the website. If a user used the     'Copy as cURL' feature and pasted the command into a     terminal, it could have resulted in command injection     and arbitrary command execution.Note: this issue     only affects Firefox on Windows operating systems.
    (CVE-2020-12393)

  - A logic flaw in our location bar implementation could     have allowed a local attacker to spoof the current     location by selecting a different origin and removing     focus from the input element. (CVE-2020-12394)

  - Mozilla developers and community members Alexandru     Michis, Jason Kratzer, philipp, Ted Campbell, Bas     Schouten, Andr Bargull, and Karl Tomlinson reported     memory safety bugs present in Firefox 75 and Firefox ESR     68.7. Some of these bugs showed evidence of memory     corruption and we presume that with enough effort some     of these could have been exploited to run arbitrary     code. (CVE-2020-12395)

  - Mozilla developers and community members Frederik Braun,     Andrew McCreight, C.M.Chang, and Dan Minor reported     memory safety bugs present in Firefox 75. Some of these     bugs showed evidence of memory corruption and we presume     that with enough effort some of these could have been     exploited to run arbitrary code. (CVE-2020-12396)

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 macOS or Mac OS X host is prior to 76.0. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2020-16 advisory.

  - A race condition when running shutdown code for Web     Worker led to a use-after-free vulnerability. This     resulted in a potentially exploitable crash.
    (CVE-2020-12387)

  - The Firefox content processes did not sufficiently     lockdown access control which could result in a sandbox     escape.Note: this issue only affects Firefox on     Windows operating systems. (CVE-2020-12388,     CVE-2020-12389)

  - A buffer overflow could occur when parsing and     validating SCTP chunks in WebRTC. This could have led to     memory corruption and a potentially exploitable crash.
    (CVE-2020-6831)

  - Incorrect origin serialization of URLs with IPv6     addresses could lead to incorrect security checks     (CVE-2020-12390)

  - Documents formed using data: URLs in an     object element failed to inherit the CSP of     the creating context. This allowed the execution of     scripts that should have been blocked, albeit with a     unique opaque origin. (CVE-2020-12391)

  - The 'Copy as cURL' feature of Devtools' network tab did     not properly escape the HTTP POST data of a request,     which can be controlled by the website. If a user used     the 'Copy as cURL' feature and pasted the command into a     terminal, it could have resulted in the disclosure of     local files. (CVE-2020-12392)

  - The 'Copy as cURL' feature of Devtools' network tab did     not properly escape the HTTP method of a request, which     can be controlled by the website. If a user used the     'Copy as cURL' feature and pasted the command into a     terminal, it could have resulted in command injection     and arbitrary command execution.Note: this issue     only affects Firefox on Windows operating systems.
    (CVE-2020-12393)

  - A logic flaw in our location bar implementation could     have allowed a local attacker to spoof the current     location by selecting a different origin and removing     focus from the input element. (CVE-2020-12394)

  - Mozilla developers and community members Alexandru     Michis, Jason Kratzer, philipp, Ted Campbell, Bas     Schouten, Andr Bargull, and Karl Tomlinson reported     memory safety bugs present in Firefox 75 and Firefox ESR     68.7. Some of these bugs showed evidence of memory     corruption and we presume that with enough effort some     of these could have been exploited to run arbitrary     code. (CVE-2020-12395)

  - Mozilla developers and community members Frederik Braun,     Andrew McCreight, C.M.Chang, and Dan Minor reported     memory safety bugs present in Firefox 75. Some of these     bugs showed evidence of memory corruption and we presume     that with enough effort some of these could have been     exploited to run arbitrary code. (CVE-2020-12396)

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
223342	Linux Distros Unpatched Vulnerability : CVE-2020-12391	Nessus	Misc.	high
136420	Ubuntu 16.04 LTS / 18.04 LTS / 20.04 LTS : Firefox vulnerabilities (USN-4353-1)	Nessus	Ubuntu Local Security Checks	critical
136404	Mozilla Firefox < 76.0	Nessus	Windows	critical
136403	Mozilla Firefox < 76.0	Nessus	MacOS X Local Security Checks	critical

Detections

Analytics

CVE-2020-12391

high

Tenable Plugins

high

critical

critical

critical