An XSS bug in internal error pages could have led to various spoofing attacks, including other error pages and the address bar. Note: This issue only affected Firefox for Android. Other operating systems are unaffected. This vulnerability affects Firefox < 85.

There are packages installed that are affected by multiple vulnerabilities referenced in the following CVEs:

  - Mozilla developers reported memory safety bugs present in Firefox 84. 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. This vulnerability affects Firefox < 85. (CVE-2021-23965)

  - Using the new logical assignment operators in a JavaScript switch statement could have caused a type
    confusion, leading to a memory corruption and a potentially exploitable crash. This vulnerability affects
    Firefox < 85, Thunderbird < 78.7, and Firefox ESR < 78.7. (CVE-2021-23954)

  - The browser could have been confused into transferring a pointer lock state into another tab, which could
    have lead to clickjacking attacks. This vulnerability affects Firefox < 85. (CVE-2021-23955)

  - An ambiguous file picker design could have confused users who intended to select and upload a single file
    into uploading a whole directory. This was addressed by adding a new prompt. This vulnerability affects
    Firefox < 85. (CVE-2021-23956)

  - Navigations through the Android-specific `intent` URL scheme could have been misused to escape iframe
    sandbox. Note: This issue only affected Firefox for Android. Other operating systems are unaffected. This
    vulnerability affects Firefox < 85. (CVE-2021-23957)

The version of Firefox installed on the remote macOS or Mac OS X host is prior to 85.0. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2021-03 advisory.

  - Mozilla developers Sebastian Hengst, Christian Holler, Tyson Smith reported memory safety bugs present in     Firefox 84. 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-2021-23965)

  - If a user clicked into a specifically crafted PDF, the PDF reader could be confused into leaking cross-     origin information, when said information is served as chunked data. (CVE-2021-23953)

  - Using the new logical assignment operators in a JavaScript switch statement could have caused a type     confusion, leading to a memory corruption and a potentially exploitable crash. (CVE-2021-23954)

  - The browser could have been confused into transferring a pointer lock state into another tab, which could     have lead to clickjacking attacks. (CVE-2021-23955)

  - An ambiguous file picker design could have confused users who intended to select and upload a single file     into uploading a whole directory. This was addressed by adding a new prompt. (CVE-2021-23956)

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 85.0. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2021-03 advisory.

  - Mozilla developers Sebastian Hengst, Christian Holler, Tyson Smith reported memory safety bugs present in     Firefox 84. 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-2021-23965)

  - If a user clicked into a specifically crafted PDF, the PDF reader could be confused into leaking cross-     origin information, when said information is served as chunked data. (CVE-2021-23953)

  - Using the new logical assignment operators in a JavaScript switch statement could have caused a type     confusion, leading to a memory corruption and a potentially exploitable crash. (CVE-2021-23954)

  - The browser could have been confused into transferring a pointer lock state into another tab, which could     have lead to clickjacking attacks. (CVE-2021-23955)

  - An ambiguous file picker design could have confused users who intended to select and upload a single file     into uploading a whole directory. This was addressed by adding a new prompt. (CVE-2021-23956)

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

ID	Name	Product	Family	Severity
426999	Alpine: multiple librewolf packages: security update to 85.0-r0	Tenable Cloud Security	Alpine Linux Local Security Checks	high
426999	Alpine: multiple librewolf packages: security update to 85.0-r0	Tenable Self-Hosted Container Security	Alpine Linux Local Security Checks	high
404378	Alpine: multiple firefox packages: security update to 85.0-r0	Tenable Cloud Security	Alpine Linux Local Security Checks	high
404378	Alpine: multiple firefox packages: security update to 85.0-r0	Tenable Self-Hosted Container Security	Alpine Linux Local Security Checks	high
145466	Mozilla Firefox < 85.0	Nessus	MacOS X Local Security Checks	high
145465	Mozilla Firefox < 85.0	Nessus	Windows	high

Detections

Analytics

CVE-2021-23959

medium

Tenable Plugins

high

high

high

high

high

high