A malicious extension could have called <code>browser.identity.launchWebAuthFlow</code>, controlling the redirect_uri, and through the Promise returned, obtain the Auth code and gain access to the user's account at the service provider. This vulnerability affects Firefox < 75.

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

  - A malicious extension could have called <code>browser.identity.launchWebAuthFlow</code>, controlling the     redirect_uri, and through the Promise returned, obtain the Auth code and gain access to the user's account     at the service provider. This vulnerability affects Firefox < 75. (CVE-2020-6823)

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

The remote host is affected by the vulnerability described in GLSA-202004-11 (Mozilla Firefox: Multiple vulnerabilities)

    Multiple vulnerabilities have been discovered in Mozilla Firefox. Please       review the CVE identifiers referenced below for details.
  Impact :

    A remote attacker could entice a user to view a specially crafted web       page, possibly resulting in the execution of arbitrary code with the       privileges of the process, an information leak or a Denial of Service       condition.
  Workaround :

    There is no known workaround at this time.

The remote Ubuntu 16.04 LTS / 18.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-4323-1 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, obtain     sensitive information, or execute arbitrary code. (CVE-2020-6821, CVE-2020-6822, CVE-2020-6824,     CVE-2020-6825, CVE-2020-6826)

    It was discovered that extensions could obtain auth codes from OAuth login flows in some circumstances. If     a user were tricked in to installing a specially crafted extension, an attacker could potentially exploit     this to obtain access to the user's account. (CVE-2020-6823)

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 75.0. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2020-12 advisory. 

  - Mozilla developers and community members Tyson Smith and Christian Holler reported     memory safety bugs present in Firefox 74 and Firefox ESR 68.6. 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-2020-6825) 

  - When reading from areas partially or fully outside the source resource with WebGL's     copyTexSubImage method, the specification requires the returned values be zero.     Previously, this memory was uninitialized, leading to potentially sensitive data     disclosure. (CVE-2020-6821)

  - On 32-bit builds, an out of bounds write could have occurred when processing an image     larger than 4 GB in GMPDecodeData. It is possible that with enough effort this could     have been exploited to run arbitrary code. (CVE-2020-6822) 

  - A malicious extension could have called browser.identity.launchWebAuthFlow,     controlling the redirect_uri, and through the Promise returned, obtain the Auth     code and gain access to the user's account at the service provider. (CVE-2020-6823)

  - Initially, a user opens a Private Browsing Window and generates a password for a site,     then closes the Private Browsing Window but leaves Firefox open. Subsequently, if the     user had opened a new Private Browsing Window, revisited the same site, and generated     a new password - the generated passwords would have been identical, rather than     independent. (CVE-2020-6824) 

  - Mozilla developers Tyson Smith, Bob Clary, and Alexandru Michis reported memory     safety bugs present in Firefox 74. 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-2020-6826)

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 75.0. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2020-12 advisory. 

  - Mozilla developers and community members Tyson Smith and Christian Holler reported     memory safety bugs present in Firefox 74 and Firefox ESR 68.6. 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-2020-6825) 

  - When reading from areas partially or fully outside the source resource with WebGL's     copyTexSubImage method, the specification requires the returned values be zero.     Previously, this memory was uninitialized, leading to potentially sensitive data     disclosure. (CVE-2020-6821)

  - On 32-bit builds, an out of bounds write could have occurred when processing an image     larger than 4 GB in GMPDecodeData. It is possible that with enough effort this could     have been exploited to run arbitrary code. (CVE-2020-6822) 

  - A malicious extension could have called browser.identity.launchWebAuthFlow,     controlling the redirect_uri, and through the Promise returned, obtain the Auth     code and gain access to the user's account at the service provider. (CVE-2020-6823)

  - Initially, a user opens a Private Browsing Window and generates a password for a site,     then closes the Private Browsing Window but leaves Firefox open. Subsequently, if the     user had opened a new Private Browsing Window, revisited the same site, and generated     a new password - the generated passwords would have been identical, rather than     independent. (CVE-2020-6824) 

  - Mozilla developers Tyson Smith, Bob Clary, and Alexandru Michis reported memory     safety bugs present in Firefox 74. 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-2020-6826)

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
230237	Linux Distros Unpatched Vulnerability : CVE-2020-6823	Nessus	Misc.	critical
135947	GLSA-202004-11 : Mozilla Firefox: Multiple vulnerabilities	Nessus	Gentoo Local Security Checks	critical
135284	Ubuntu 16.04 LTS / 18.04 LTS : Firefox vulnerabilities (USN-4323-1)	Nessus	Ubuntu Local Security Checks	critical
135276	Mozilla Firefox < 75.0 (mfsa2020-12)	Nessus	Windows	critical
135275	Mozilla Firefox < 75.0 Multiple Vulnerabilities (mfsa2020-12)	Nessus	MacOS X Local Security Checks	critical

Detections

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CVE-2020-6823

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Tenable Plugins

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