Use-after-free while manipulating the "navigator" object within WebVR. Note: WebVR is not currently enabled by default. This vulnerability affects Firefox < 50.1.

A race condition when running shutdown code for Web Worker led to a use-after-free vulnerability. This resulted in a potentially exploitable crash. This vulnerability affects Firefox ESR < 68.8, Firefox < 76, and Thunderbird < 68.8.0.

A use-after-free vulnerability can occur in AssertWorkerThread due to a race condition with shared workers. This results in a potentially exploitable crash. This vulnerability affects Firefox < 67.

When interacting with an HTML input element's file picker dialog with webkitdirectory set, a use-after-free could have resulted, leading to memory corruption and a potentially exploitable crash. This vulnerability affects Firefox < 94, Thunderbird < 91.3, and Firefox ESR < 91.3.

Mozilla developers reported memory safety bugs present in Firefox 70. 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 < 71.

When following the value's prototype chain, it was possible to retain a reference to a locale, delete it, and subsequently reference it. This resulted in a use-after-free and a potentially exploitable crash. This vulnerability affects Firefox < 70, Thunderbird < 68.2, and Firefox ESR < 68.2.

A use-after-free vulnerability can occur while manipulating video elements if the body is freed while still in use. This results in a potentially exploitable crash. This vulnerability affects Firefox < 69, Thunderbird < 68.1, Thunderbird < 60.9, Firefox ESR < 60.9, and Firefox ESR < 68.1.

Improper refcounting of soft token session objects could cause a use-after-free and crash (likely limited to a denial of service). This vulnerability affects Firefox < 71.

When using nested workers, a use-after-free could occur during worker destruction. This resulted in a potentially exploitable crash. This vulnerability affects Thunderbird < 68.3, Firefox ESR < 68.3, and Firefox < 71.

A use-after-free vulnerability in media channels could have led to memory corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 78.13, Thunderbird < 91, Firefox ESR < 78.13, and Firefox < 91.

Under certain conditions, when running the nsDocShell destructor, a race condition can cause a use-after-free. We are aware of targeted attacks in the wild abusing this flaw. This vulnerability affects Thunderbird < 68.7.0, Firefox < 74.0.1, and Firefox ESR < 68.6.1.

When a device was changed while a stream was about to be destroyed, the <code>stream-reinit</code> task may have been executed after the stream was destroyed, causing a use-after-free and a potentially exploitable crash. This vulnerability affects Thunderbird < 68.6, Firefox < 74, Firefox < ESR68.6, and Firefox ESR < 68.6.

A use-after-free vulnerability can occur when script uses mutation events to move DOM nodes between documents, resulting in the old document that held the node being freed but the node still having a pointer referencing it. This results in a potentially exploitable crash. This vulnerability affects Thunderbird < 60, Thunderbird < 52.9, Firefox ESR < 60.1, Firefox ESR < 52.9, and Firefox < 61.

Use-after-free vulnerability in Mozilla Firefox before 17.0, Firefox ESR 10.x before 10.0.11, Thunderbird before 17.0, Thunderbird ESR 10.x before 10.0.11, and SeaMonkey before 2.14 on Mac OS X allows remote attackers to execute arbitrary code via an HTML document.

A use-after-free vulnerability during specific user interactions with the input method editor (IME) in some languages due to how events are handled. This results in a potentially exploitable crash but would require specific user interaction to trigger. This vulnerability affects Firefox < 54, Firefox ESR < 52.2, and Thunderbird < 52.2.

A use-after-free vulnerability can occur when deleting an input element during a mutation event handler triggered by focusing that element. This results in a potentially exploitable crash. This vulnerability affects Thunderbird < 60, Thunderbird < 52.9, Firefox ESR < 60.1, Firefox ESR < 52.9, and Firefox < 61.

A use-after-free could have occured when an HTTP2 session object was released on a different thread, leading to memory corruption and a potentially exploitable crash. This vulnerability affects Firefox < 93, Thunderbird < 91.3, and Firefox ESR < 91.3.

Use-after-free vulnerability in the nsNodeUtils::NativeAnonymousChildListChange function in Mozilla Firefox before 48.0 and Firefox ESR 45.x before 45.3 allows remote attackers to execute arbitrary code or cause a denial of service (heap memory corruption) via an SVG element that is mishandled during effect application.

Failure to correctly record the location of live pointers across wasm instance calls resulted in a GC occurring within the call not tracing those live pointers. This could have led to a use-after-free causing a potentially exploitable crash. This vulnerability affects Thunderbird < 91.4.0, Firefox ESR < 91.4.0, and Firefox < 95.

A use-after-free vulnerability was found via testing, and traced to an out-of-date Cairo library. Updating the library resolved the issue, and may have remediated other, unknown security vulnerabilities as well. This vulnerability affects Firefox < 90.

During browser shutdown, reference decrementing could have occured on a previously freed object, resulting in a use-after-free, memory corruption, and a potentially exploitable crash. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.

Mozilla developers reported memory safety bugs present in Firefox for Android 79. 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 < 80, Firefox ESR < 78.2, Thunderbird < 78.2, and Firefox for Android < 80.

When recursing through graphical layers while scrolling, an iterator may have become invalid, resulting in a potential use-after-free. This occurs because the function APZCTreeManager::ComputeClippedCompositionBounds did not follow iterator invalidation rules. This vulnerability affects Firefox < 81, Thunderbird < 78.3, and Firefox ESR < 78.3.

When aborting an operation, such as a fetch, an abort signal may be deleted while alerting the objects to be notified. This results in a use-after-free and we presume that with enough effort it could have been exploited to run arbitrary code. This vulnerability affects Firefox ESR < 68.12 and Thunderbird < 68.12.

When processing surfaces, the lifetime may outlive a persistent buffer leading to memory corruption and a potentially exploitable crash. This vulnerability affects Firefox < 81.

A use-after-free in nsINode::ReplaceOrInsertBefore during DOM operations resulting in potentially exploitable crashes. This vulnerability affects Firefox < 50.

Use-after-free vulnerability in the CanonicalizeXPCOMParticipant function in Mozilla Firefox before 48.0 and Firefox ESR 45.x before 45.3 allows remote attackers to execute arbitrary code via a script that closes its own Service Worker within a nested sync event loop.

Use-after-free vulnerability in the WebRTC socket thread in Mozilla Firefox before 48.0 and Firefox ESR 45.x before 45.3 allows remote attackers to execute arbitrary code by leveraging incorrect free operations on DTLS objects during the shutdown of a WebRTC session.

When removing data about an origin whose tab was recently closed, a use-after-free could occur in the Quota manager, resulting in a potentially exploitable crash. This vulnerability affects Thunderbird < 68.6, Firefox < 74, Firefox < ESR68.6, and Firefox ESR < 68.6.

Mozilla developers reported memory safety bugs present in Firefox 80 and Firefox ESR 78.2. 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 < 81, Thunderbird < 78.3, and Firefox ESR < 78.3.

During operations on MessageTasks, a task may have been removed while it was still scheduled, resulting in memory corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 78.15, Thunderbird < 91.2, Firefox ESR < 91.2, Firefox ESR < 78.15, and Firefox < 93.

When using certain blank characters in a URL, they where incorrectly rendered as spaces instead of an encoded URL. This vulnerability affects Firefox < 77.

Use-after-free vulnerability in the mozilla::dom::IndexedDB::IDBObjectStore::CreateIndex function in Mozilla Firefox before 36.0, Firefox ESR 31.x before 31.5, and Thunderbird before 31.5 allows remote attackers to execute arbitrary code or cause a denial of service (heap memory corruption) via crafted content that is improperly handled during IndexedDB index creation.

The asm.js implementation in Mozilla Firefox before 36.0.3, Firefox ESR 31.x before 31.5.2, and SeaMonkey before 2.33.1 does not properly determine the cases in which bounds checking may be safely skipped during JIT compilation and heap access, which allows remote attackers to read or write to unintended memory locations, and consequently execute arbitrary code, via crafted JavaScript.

Multiple cross-site scripting (XSS) vulnerabilities in (1) editcomponents.cgi, (2) editgroups.cgi, (3) editmilestones.cgi, (4) editproducts.cgi, (5) editusers.cgi, and (6) editversions.cgi in Bugzilla 2.16.x before 2.16.6, and 2.18 before 2.18rc1, allow remote attackers to execute arbitrary JavaScript as other users via a URL parameter.

Mozilla before 1.4.2 executes Javascript events in the context of a new page while it is being loaded, allowing it to interact with the previous page (zombie document) and enable cross-domain and cross-site scripting (XSS) attacks, as demonstrated using onmousemove events.

Mozilla developers and community members reported memory safety bugs present in Firefox 86 and Firefox ESR 78.8. 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 ESR < 78.9, Firefox < 87, and Thunderbird < 78.9.

Cross-site scripting vulnerabilities (XSS) in bonsai Mozilla CVS query tool allow remote attackers to execute arbitrary web script via (1) the file, root, or rev parameters to cvslog.cgi, (2) the file or root parameters to cvsblame.cgi, (3) various parameters to cvsquery.cgi, (4) the person parameter to showcheckins.cgi, (5) the module parameter to cvsqueryform.cgi, and (6) possibly other attack vectors as identified by Mozilla bug #146244.

Multiple cross-site scripting vulnerabilities (XSS) in Bugzilla 2.16.x before 2.16.3 and 2.17.x before 2.17.4 allow remote attackers to insert arbitrary HTML or web script via (1) multiple default German and Russian HTML templates or (2) ALT and NAME attributes in AREA tags as used by the GraphViz graph generation feature for local dependency graphs.

Multiple unspecified vulnerabilities in the browser engine in Mozilla Firefox before 34.0, Firefox ESR 31.x before 31.3, Thunderbird before 31.3, and SeaMonkey before 2.31 allow remote attackers to cause a denial of service (memory corruption and application crash) or possibly execute arbitrary code via unknown vectors.

Use-after-free vulnerability in the nsHtml5TreeOperation function in xul.dll in Mozilla Firefox before 34.0, Firefox ESR 31.x before 31.3, Thunderbird before 31.3, and SeaMonkey before 2.31 allows remote attackers to execute arbitrary code by adding a second root element to an HTML5 document during parsing.

Multiple unspecified vulnerabilities in the browser engine in Mozilla Firefox before 27.0, Firefox ESR 24.x before 24.3, Thunderbird before 24.3, and SeaMonkey before 2.24 allow remote attackers to cause a denial of service (memory corruption and application crash) or possibly execute arbitrary code via unknown vectors.

Stack-based buffer overflow in the mozilla::FileBlockCache::Read function in Mozilla Firefox before 34.0, Firefox ESR 31.x before 31.3, Thunderbird before 31.3, and SeaMonkey before 2.31 allows remote attackers to execute arbitrary code via crafted media content.

Mozilla Firefox before 34.0 and SeaMonkey before 2.31 provide stylesheets with an incorrect primary namespace, which allows remote attackers to bypass intended access restrictions via an XBL binding.

Canvas allows the use of the "feDisplacementMap" filter on images loaded cross-origin. The rendering by the filter is variable depending on the input pixel, allowing for timing attacks when the images are loaded from third party locations. This vulnerability affects Firefox < 50.

Buffer overflow in the Speex resampler in the Web Audio subsystem in Mozilla Firefox before 30.0 allows remote attackers to execute arbitrary code via vectors related to a crafted AudioBuffer channel count and sample rate.

Mozilla developers reported memory safety bugs present in Firefox 92 and Firefox ESR 91.1. 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 < 93, Thunderbird < 91.2, and Firefox ESR < 91.2.

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.*. This vulnerability affects Thunderbird < 60.7, Firefox < 67, and Firefox ESR < 60.7.

Incorrect handling of __proto__ mutations may lead to type confusion in IonMonkey JIT code and can be leveraged for arbitrary memory read and write. This vulnerability affects Firefox < 66.0.1, Firefox ESR < 60.6.1, and Thunderbird < 60.6.1.