==================================================================== CERT-Renater Note d'Information No. 2021/VULN049 _____________________________________________________________________ DATE : 27/01/2021 HARDWARE PLATFORM(S): / OPERATING SYSTEM(S): Systems running Firefox versions prior to 85, ESR 78.7. ===================================================================== https://www.mozilla.org/en-US/security/advisories/mfsa2021-03/ https://www.mozilla.org/en-US/security/advisories/mfsa2021-04/ _____________________________________________________________________ Mozilla Foundation Security Advisory 2021-03 Security Vulnerabilities fixed in Firefox 85 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 nsTreeBodyFrame::RowCountChanged 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 _____________________________________________________________________ Mozilla Foundation Security Advisory 2021-04 Security Vulnerabilities fixed in Firefox ESR 78.7 Announced January 26, 2021 Impact high Products Firefox ESR Fixed in Firefox ESR 78.7 #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-2020-26976: HTTPS pages could have been intercepted by a registered service worker when they should not have been Reporter Andrew Sutherland Impact moderate Description When a HTTPS page was embedded in a HTTP page, and there was a service worker registered for the former, the service worker could have intercepted the request for the secure page despite the iframe not being a secure context due to the (insecure) framing. References Bug 1674343 #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-2021-23964: Memory safety bugs fixed in Firefox 85 and Firefox ESR 78.7 Reporter Mozilla developers and community Impact high Description Mozilla developers Alexis Beingessner, Christian Holler, Andrew McCreight, Tyson Smith, Jon Coppeard, André Bargull, Jason Kratzer, Jesse Schwartzentruber, Steve Fink, Byron Campen 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 ========================================================= + CERT-RENATER | tel : 01-53-94-20-44 + + 23/25 Rue Daviel | fax : 01-53-94-20-41 + + 75013 Paris | email:cert@support.renater.fr + =========================================================