entially risks in browser or browser-like contexts.
#CVE-2019-9815: Disable hyperthreading on content JavaScript threads on macOS

Reporter
    Multiple independent researchers
Impact
    high

Description

If hyperthreading is not disabled, a timing attack vulnerability exists, similar to previous Spectre attacks. Apple has shipped macOS 10.14.5 with an option to disable hyperthreading in applications running untrusted code in a thread through a new sysctl. Firefox now makes use of it on the main thread and any worker threads.
Note: users need to update to macOS 10.14.5 in order to take advantage of this change.
References

    Bug 1546544
    RIDL and Fallout: MDS attacks

#CVE-2019-9816: Type confusion with object groups and UnboxedObjects

Reporter
    Samuel Groß of Google Project Zero
Impact
    high

Description

A possible vulnerability exists where type confusion can occur when manipulating JavaScript objects in object groups, allowing for the bypassing of security checks within these groups.
Note: this vulnerability has only been demonstrated with UnboxedObjects, which are disabled by default on all supported releases.
References

    Bug 1536768

#CVE-2019-9817: Stealing of cross-domain images using canvas

Reporter
    Luật Nguyễn
Impact
    high

Description

Images from a different domain can be read using a canvas object in some circumstances. This could be used to steal image data from a different site in violation of same-origin policy.
References

    Bug 1540221

#CVE-2019-9818: Use-after-free in crash generation server

Reporter
    Thomas Imbert
Impact
    high

Description

A race condition is present in the crash generation server used to generate data for the crash reporter. This issue can lead to a use-after-free in the main process, resulting in a potentially exploitable crash and a sandbox escape.
Note: this vulnerability only affects Windows. Other operating systems are unaffected.
References

    Bug 1542581

#CVE-2019-9819: Compartment mismatch with fetch API

Reporter
    Nils
Impact
    high

Description

A vulnerability where a JavaScript compartment mismatch can occur while working with the fetch API, resulting in a potentially exploitable crash.
References

    Bug 1532553

#CVE-2019-9820: Use-after-free of ChromeEventHandler by DocShell

Reporter
    Nils
Impact
    high

Description

A use-after-free vulnerability can occur in the chrome event handler when it is freed while still in use. This results in a potentially exploitable crash.
References

    Bug 1536405

#CVE-2019-11691: Use-after-free in XMLHttpRequest

Reporter
    Nils
Impact
    high

Description

A use-after-free vulnerability can occur when working with XMLHttpRequest (XHR) in an event loop, causing the XHR main thread to be called after it has been freed. This results in a potentially exploitable crash.
References

    Bug 1542465

#CVE-2019-11692: Use-after-free removing listeners in the event listener manager

Reporter
    Nils
Impact
    high

Description

A use-after-free vulnerability can occur when listeners are removed from the event listener manager while still in use, resulting in a potentially exploitable crash.
References

    Bug 1544670

#CVE-2019-11693: Buffer overflow in WebGL bufferdata on Linux

Reporter
    crixer
Impact
    high

Description

The bufferdata function in WebGL is vulnerable to a buffer overflow with specific graphics drivers on Linux. This could result in malicious content freezing a tab or triggering a potentially exploitable crash.
Note: this issue only occurs on Linux. Other operating systems are unaffected.
References

    Bug 1532525

#CVE-2019-7317: Use-after-free in png_image_free of libpng library

Reporter
    OSS-Fuzz, Eddie Lee
Impact
    high

Description

A use-after-free vulnerability was discovered in the png_image_free function in the libpng library. This could lead to denial of service or a potentially exploitable crash when a malformed image is processed.
References

    Bug 1542829

#CVE-2019-9797: Cross-origin theft of images with createImageBitmap

Reporter
    AaylaSecura1138
Impact
    high

Description

Cross-origin images can be read in violation of the same-origin policy by exporting an image after using createImageBitmap to read the image and then rendering the resulting bitmap image within a canvas element.
References

    Bug 1528909

#CVE-2018-18511: Cross-origin theft of images with ImageBitmapRenderingContext

Reporter
    AaylaSecura1138
Impact
    high

Description

Cross-origin images can be read from a canvas element in violation of the same-origin policy using the transferFromImageBitmap method.
References

    Bug 1526218

#CVE-2019-11694: Uninitialized memory memory leakage in Windows sandbox

Reporter
    Jeremy Fetiveau of SSD Secure Disclosure
Impact
    moderate

Description

A vulnerability exists in the Windows sandbox where an uninitialized value in memory can be leaked to a renderer from a broker when making a call to access an otherwise unavailable file. This results in the potential leaking of information stored at that memory location.
Note: this issue only occurs on Windows. Other operating systems are unaffected.
References

    Bug 1534196

#CVE-2019-11698: Theft of user history data through drag and drop of hyperlinks to and from bookmarks

Reporter
    Abdulrahman Alqabandi
Impact
    moderate

Description

If a crafted hyperlink is dragged and dropped to the bookmark bar or sidebar and the resulting bookmark is subsequently dragged and dropped into the web content area, an arbitrary query of a user's browser history can be run and transmitted to the content page via drop event data. This allows for the theft of browser history by a malicious site.
References

    Bug 1543191

#CVE-2019-5798: Out-of-bounds read in Skia

Reporter
    Tran Tien Hung of Viettel Cyber Security
Impact
    moderate

Description

An out-of-bounds read can occur in the Skia library during path transformations. This could result in the exposure of data stored in memory.
References

    Bug 1535518

#CVE-2019-9800: Memory safety bugs fixed in Firefox 67, Firefox ESR 60.7, and Thunderbird 60.7

Reporter
    Mozilla developers and community
Impact
    critical

Description

Mozilla developers and community members Olli Pettay, Bogdan Tara, Jan de Mooij, Jason Kratzer, Jan Varga, Gary Kwong, Tim Guan-tin Chien, Tyson Smith, Ronald Crane, and Ted Campbell reported memory safety bugs present in Firefox 66, Firefox ESR 60.6, and Thunderbird 60.6. Some of these