Headline
CVE-2021-23961: Security Vulnerabilities fixed in Firefox 85
Further techniques that built on the slipstream research combined with a malicious webpage could have exposed both an internal network’s hosts as well as services running on the user’s local machine. This vulnerability affects Firefox < 85.
Mozilla Foundation Security Advisory 2021-03
Announced
January 26, 2021
Impact
high
Products
Firefox
Fixed in
- Firefox 85
#CVE-2021-23953: Cross-origin information leakage via redirected PDF requests
Reporter
Rob Wu
Impact
high
Description
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.
References
- Bug 1683940
#CVE-2021-23954: Type confusion when using logical assignment operators in JavaScript switch statements
Reporter
Gary Kwong
Impact
high
Description
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.
References
- Bug 1684020
#CVE-2021-23955: Clickjacking across tabs through misusing requestPointerLock
Reporter
Irvan Kurniawan
Impact
high
Description
The browser could have been confused into transferring a pointer lock state into another tab, which could have lead to clickjacking attacks.
References
- Bug 1684837
#CVE-2021-23956: File picker dialog could have been used to disclose a complete directory
Reporter
Abdulrahman Alqabandi
Impact
moderate
Description
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.
References
- Bug 1338637
#CVE-2021-23957: Iframe sandbox could have been bypassed on Android via the intent URL scheme
Reporter
Eliya Stein
Impact
moderate
Description
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.
References
- Bug 1584582
#CVE-2021-23958: Screen sharing permission leaked across tabs
Reporter
Jan-Ivar Bruaroey
Impact
moderate
Description
The browser could have been confused into transferring a screen sharing state into another tab, which would leak unintended information.
References
- Bug 1642747
#CVE-2021-23959: Cross-Site Scripting in error pages on Firefox for Android
Reporter
Muneaki Nishimura
Impact
moderate
Description
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.
References
- Bug 1659035
#CVE-2021-23960: Use-after-poison for incorrectly redeclared JavaScript variables during GC
Reporter
Irvan Kurniawan
Impact
moderate
Description
Performing garbage collection on re-declared JavaScript variables resulted in a user-after-poison, and a potentially exploitable crash.
References
- Bug 1675755
#CVE-2021-23961: More internal network hosts could have been probed by a malicious webpage
Reporter
Samy Kamkar, Ben Seri, and Gregory Vishnepolsky
Impact
moderate
Description
Further techniques that built on the slipstream research combined with a malicious webpage could have exposed both an internal network’s hosts as well as services running on the user’s local machine.
References
- Bug 1677940
#CVE-2021-23962: Use-after-poison in <code>nsTreeBodyFrame::RowCountChanged</code>
Reporter
Chiaki ISHIKAWA
Impact
low
Description
Incorrect use of the RowCountChanged method could have led to a user-after-poison and a potentially exploitable crash.
References
- Bug 1677194
#CVE-2021-23963: Permission prompt inaccessible after asking for additional permissions
Reporter
Paul Zühlcke
Impact
low
Description
When sharing geolocation during an active WebRTC share, Firefox could have reset the webRTC sharing state in the user interface, leading to loss of control over the currently granted permission
References
- Bug 1680793
#CVE-2021-23964: Memory safety bugs fixed in Firefox 85 and Firefox ESR 78.7
Reporter
Mozilla developers and community
Impact
high
Description
Mozilla developers Andrew McCreight, Tyson Smith, Jesse Schwartzentruber, Jon Coppeard, Byron Campen, André Bargull, Steve Fink, Jason Kratzer, Christian Holler, Alexis Beingessner reported memory safety bugs present in Firefox 84 and Firefox ESR 78.6. 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.
References
- Memory safety bugs fixed in Firefox 85 and Firefox ESR 78.7
#CVE-2021-23965: Memory safety bugs fixed in Firefox 85
Reporter
Mozilla developers and community
Impact
high
Description
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.
References
- Memory safety bugs fixed in Firefox 85