JSDependentString::undepend string conversion results in memory corruption — Mozilla

Security researcher Bill Keese reported a memory corruption. This is caused by JSDependentString::undepend changing a dependent string into a fixed string when there are additional dependent strings relying on the same base. When the undepend occurs during conversion, the base data is freed,...

WebGL.drawElements may read illegal video memory due to FindMaxUshortElement error — Mozilla

Mozilla community member Matias Juntunen discovered an error in WebGLBuffer where FindMaxElementInSubArray receives wrong template arguments from FindMaxUshortElement. This bug causes maximum index to be computed incorrectly within WebGL.drawElements, allowing the reading of illegal video memory...

Frame scripts calling into untrusted objects bypass security checks — Mozilla

Mozilla security researcher mozbugra4 reported that frame scripts bypass XPConnect security checks when calling untrusted objects. This allows for cross-site scripting XSS attacks through web pages and Firefox extensions. The fix enables the Script Security Manager SSM to force security checks on...

Miscellaneous memory safety hazards (rv:10.0/ 1.9.2.26) — Mozilla

Mozilla developers identified and fixed several memory safety bugs in the browser engine used in Firefox and other Mozilla-based products. Some of these bugs showed evidence of memory corruption under certain circumstances, and we presume that with enough effort at least some of these could be...

Potential XSS against sites using Shift-JIS — Mozilla

Yosuke Hasegawa reported that the Mozilla browser engine mishandled invalid sequences in the Shift-JIS encoding. When encountering an invalid pair Mozilla would turn the entire two-byte sequence into a single unknown character rather than an unknown character followed by a valid single-byte...

Heap buffer overflow in nsGenericDOMDataNode::SetTextInternal — Mozilla

Security researcher Nils of MWR InfoSecurity reported that the routine for setting the text value for certain types of DOM nodes contained an integer overflow vulnerability. When a very long string was passed to this routine, the integer value used in creating a new memory buffer to hold the stri...

Update NSS to support TLS renegotiation indication — Mozilla

Mozilla developers added support in the Network Security Services module for preventing a type of man-in-the-middle attack against TLS using forced renegotiation...

Crashes with evidence of memory corruption (rv:1.9.1/1.9.0.12) — Mozilla

Mozilla developers and community members identified and fixed several stability bugs in the browser engine used in Firefox and other Mozilla-based products. Some of these crashes showed evidence of memory corruption under certain circumstances and we presume that with enough effort at least some ...

Mishandling of locally-saved plain text files — Mozilla

Mozilla contributor oo.rio.oo demonstrated that once a file with Content-Disposition: attachment and improper Content-Type: plain/text is saved locally, the browser would no longer open local files with .txt extensions for viewing, but would rather prompt the user to save the file...

Security Vulnerabilities fixed in Firefox ESR 115.9 — Mozilla

An unchecked return value in TLS handshake code could have caused a potentially exploitable crash. An attacker could have leveraged the Windows Error Reporter to run arbitrary code on the system escaping the sandbox. Note: This issue only affected Windows operating systems. Other operating system...

Security Vulnerabilities fixed in Firefox ESR 115.7 — Mozilla

An out of bounds write in ANGLE could have allowed an attacker to corrupt memory leading to a potentially exploitable crash. It was possible for certain browser prompts and dialogs to be activated or dismissed unintentionally by the user due to an incorrect timestamp used to prevent input after...

Security Vulnerabilities fixed in Firefox ESR 91.4.0 — Mozilla

Under certain circumstances, asynchronous functions could have caused a navigation to fail but expose the target URL. An incorrect type conversion of sizes from 64bit to 32bit integers allowed an attacker to corrupt memory leading to a potentially exploitable crash. By misusing a race in our...

Security Vulnerabilities fixed in Firefox ESR 78.11 — Mozilla

A locally-installed hostile program could send WMCOPYDATA messages that Firefox would processing incorrectly, leading to an out-of-bounds read. This bug only affects Firefox on Windows. Other operating systems are unaffected. Mozilla developers Gabriele Svelto, Anny Gakhokidze, Alexandru Michis,...

Security vulnerabilities fixed in - Thunderbird 68.1 — Mozilla

Encrypted S/MIME parts in a crafted multipart/alternative message can leak plaintext when included in a a HTML reply/forward. 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. Some...

Security vulnerabilities fixed in Thunderbird 60.6 — Mozilla

A use-after-free vulnerability can occur when a raw pointer to a DOM element on a page is obtained using JavaScript and the element is then removed while still in use. This results in a potentially exploitable crash. The type inference system allows the compilation of functions that can cause typ...

Entering fullscreen and persistent pointerlock without user permission — Mozilla

Security researcher sushi Anton Larsson reported that when paired fullscreen and pointerlock requests are done in combination with closing windows, a pointerlock can be created within a fullscreen window without user permission. This pointerlock cannot then be cancelled without terminating the...

Out-of-bounds write with malicious font in Graphite 2 — Mozilla

Security researcher James Clawson used the Address Sanitizer tool to discover an out-of-bounds write in the Graphite 2 library when loading a crafted Graphite font file. This results in a potentially exploitable crash...

Miscellaneous memory safety hazards (rv:42.0 / rv:38.4) — Mozilla

Mozilla developers and community identified and fixed several memory safety bugs in the browser engine used in Firefox and other Mozilla-based products. Some of these bugs showed evidence of memory corruption under certain circumstances, and we presume that with enough effort at least some of the...

Miscellaneous memory safety hazards (rv:39.0 / rv:31.8 / rv:38.1) — Mozilla

Mozilla developers and community identified and fixed several memory safety bugs in the browser engine used in Firefox and other Mozilla-based products. Some of these bugs showed evidence of memory corruption under certain circumstances, and we presume that with enough effort at least some of the...

Buffer overflow with SVG content and CSS — Mozilla

Using the Address Sanitizer tool, security researcher Atte Kettunen found a buffer overflow during the rendering of SVG format graphics when combined with specific CSS properties on a page. This results in a potentially exploitable crash...

PRNG weakness allows for DNS poisoning on Android — Mozilla

Mozilla developer Daniel Stenberg reported that the DNS resolver in Firefox for Android uses an insufficiently random algorithm when generating random numbers for the unique identifier. This was derived from an old version of the Bionic libc library and suffered from insufficient randomness in th...

Windows can retain access to privileged content on navigation to unprivileged pages — Mozilla

Mozilla developer Bobby Holley reported that windows created to hold privileged UI content retained access to privileged internal methods if later navigated to unprivileged content. If a separate flaw was found that allowed for web content to reference these privileged windows, an attacker could...

Buffer underflow during MP3 playback — Mozilla

Security researcher Atte Kettunen used the Address Sanitizer tool to discover a buffer underflow during audio playback of a badly formatted MP3 audio files. Through memory allocation manipulation it may be possible to incorporate parts of Firefox memory into an MP3 stream accessible to scripts on...

Use-after-free in IndexedDB — Mozilla

Security researcher Paul Bandha used the used the Address Sanitizer tool to discover a use-after-free vulnerability when running specific web content with IndexedDB to create an index. This leads to a potentially exploitable crash...

Appended period to hostnames can bypass HPKP and HSTS protections — Mozilla

Security researcher Muneaki Nishimura reported that when certificate pinning is set to "strict" mode, a period '.' appended to a hostname in the address of a site allowed the bypass key pinning HPKP and HTTP Strict Transport Security HSTS. Sites with a period appended were treated as having a...

XrayWrapper bypass through DOM objects — Mozilla

Mozilla developer Bobby Holley reported that Document Object Model DOM objects with some specific properties can bypass XrayWrappers. This can allow web content to confuse privileged code, potentially enabling privilege escalation...

Further uninitialized memory use during GIF rendering — Mozilla

Google security researcher Michal Zalewski reported that when a malformed GIF image is repeatedly rendered within a element, memory may not always be properly initialized. The resulting series of images then uses this uninitialized memory during rendering, allowing data to potentially leak to web...

Android Crash Reporter open to manipulation — Mozilla

Firefox for Android includes a Crash Reporter which sends crash data to Mozilla for analysis. Security researcher Roee Hay reported that third party Android applications could launch the crash reporter with their own arguments. Normally applications cannot read the private files of another...

Out of bounds read during WAV file decoding — Mozilla

Security researcher Atte Kettunen from OUSPG reported an out of bounds read during the decoding of WAV format audio files for playback. This could allow web content access to heap data as well as causing a crash...

Use-after-free during Table Editing — Mozilla

Security researcher Nils used the Address Sanitizer tool while fuzzing to discover a use-after-free problem in the table editing user interface of the editor during garbage collection. This leads to a potentially exploitable crash...

Access violation with XSLT and uninitialized data — Mozilla

Security researcher Abhishek Arya Inferno of the Google Chrome Security Team used the Address Sanitizer tool to discover an access violation due to uninitialized data during Extensible Stylesheet Language Transformation XSLT processing. This leads to a potentially exploitable crash...

Mozilla Updater fails to update some Windows Registry entries — Mozilla

Security researcher Robert Kugler discovered that in some instances the Mozilla Maintenance Service on Windows will be vulnerable to some previously fixed privilege escalation attacks that allowed for local privilege escalation. This was caused by the Mozilla Updater not updating Windows Registry...

Privacy leak in JavaScript Workers — Mozilla

Mozilla security researcher Frederik Braun discovered that since Firefox 15 the file system location of the active browser profile was available to JavaScript workers. While not dangerous by itself, this could potentially be combined with other vulnerabilities to target the profile in an attack...

Miscellaneous memory safety hazards (rv:16.0/ rv:10.0.8) — Mozilla

Mozilla developers identified and fixed several memory safety bugs in the browser engine used in Firefox and other Mozilla-based products. Some of these bugs showed evidence of memory corruption under certain circumstances, and we presume that with enough effort at least some of these could be...

Crash with invalid cast when using instanceof operator — Mozilla

Mozilla community member Ms2ger reported a crash due to an invalid cast when using the instanceof operator on certain types of JavaScript objects. This can lead to a potentially exploitable crash...

Clickjacking of certificate warning page — Mozilla

Security Researcher Matt McCutchen reported that a clickjacking attack using the certificate warning page. A man-in-the-middle MITM attacker can use an iframe to display its own certificate error warning page about:certerror with the "Add Exception" button of a real warning page from a malicious...

Improper filtering of javascript in HTML feed-view — Mozilla

Security researcher Mario Heiderich reported that javascript could be executed in the HTML feed-view using tag within the RSS . This problem is due to tags not being filtered out during parsing and can lead to a potential cross-site scripting XSS attack. The flaw existed in a parser utility class...

NSS parsing errors with zero length items — Mozilla

Security researcher Kaspar Brand found a flaw in how the Network Security Services NSS ASN.1 decoder handles zero length items. Effects of this issue depend on the field. One known symptom is an unexploitable crash in handling OCSP responses. NSS also mishandles zero-length basic constraints,...

Multiple security flaws fixed in FreeType v2.4.9 — Mozilla

Mateusz Jurczyk of the Google Security Team used the Address Sanitizer tool to discover a series of memory safety bugs in the FreeType library, some of which could cause memory corruption and exploitable crashes with certain fonts and font parsing. Firefox Mobile has been upgraded to FreeType...

Code installation through holding down Enter — Mozilla

Mariusz Mlynski reported that if you could convince a user to hold down the Enter key--as part of a game or test, perhaps--a malicious page could pop up a download dialog where the held key would then activate the default Open action. For some file types this would be merely annoying the equivale...

Use after free reading OGG headers — Mozilla

sczimmer reported that Firefox crashed when loading a particular .ogg file. This was due to a use-after-free condition and could potentially be exploited to install malware...

Miscellaneous memory safety hazards (rv:1.9.2.11/ 1.9.1.14) — Mozilla

Mozilla developers identified and fixed several memory safety bugs in the browser engine used in Firefox and other Mozilla-based products. Some of these bugs showed evidence of memory corruption under certain circumstances, and we presume that with enough effort at least some of these could be...

Remote code execution with use-after-free in nsTreeSelection — Mozilla

Security researcher regenrecht reported via TippingPoint's Zero Day Initiative that a select event handler for XUL tree items could be called after the tree item was deleted. This results in the execution of previously freed memory which an attacker could use to crash a victim's browser and run...

Security Vulnerabilities fixed in Firefox ESR 91.9 — Mozilla

When reusing existing popups Firefox would have allowed them to cover the fullscreen notification UI, which could have enabled browser spoofing attacks. Documents in deeply-nested cross-origin browsing contexts could have obtained permissions granted to the top-level origin, bypassing the existin...

Security Vulnerabilities fixed in Firefox ESR 78.15 — Mozilla

During operations on MessageTasks, a task may have been removed while it was still scheduled, resulting in memory corruption and a potentially exploitable crash. Mozilla developers and community members Andreas Pehrson and Christian Holler reported memory safety bugs present in Firefox 92 and...

Security Vulnerabilities fixed in Thunderbird 78.2 — Mozilla

If Thunderbird is installed to a user-writable directory, the Mozilla Maintenance Service would execute updater.exe from the install location with system privileges. Although the Mozilla Maintenance Service does ensure that updater.exe is signed by Mozilla, the version could have been rolled back...

Security vulnerabilities fixed in Thunderbird 60.5.1 — Mozilla

A use-after-free vulnerability in the Skia library can occur when creating a path, leading to a potentially exploitable crash. An integer overflow vulnerability in the Skia library can occur after specific transform operations, leading to a potentially exploitable crash. A buffer overflow...

Security vulnerabilities fixed in Firefox 49 — Mozilla

A content security policy CSP containing a referrer directive with no values can cause a non-exploitable crash. An out-of-bounds write of a boolean value during text conversion with some unicode characters An out-of-bounds read during the processing of text runs in some pages using...

Use-after-free when applying SVG effects — Mozilla

Security researcher Nils used the Address Sanitizer tool to discover a use-after-free vulnerability when applying effects to SVG elements. This results in a potentially exploitable crash...

Information disclosure of disabled plugins through CSS pseudo-classes — Mozilla

Mozilla developer John Schoenick reported that CSS pseudo-classes can be used by web content to leak information on plugins that are installed but disabled. This can be used for information disclosure through a fingerprinting attack that lists all of the plugins installed by a user on a system,...