Content Security Policy inline-script bypass — Mozilla

Security researcher Adam Barth found that inline event handlers, such as onclick, were no longer blocked by Content Security Policy's CSP inline-script blocking feature. Web applications relying on this feature of CSP to protect against cross-site scripting XSS were not fully protected...

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...

Multiple dangling pointer vulnerabilities — Mozilla

Security researcher regenrecht reported several dangling pointer vulnerabilities via TippingPoint's Zero Day Initiative...

Cross-domain data theft using CSS — Mozilla

Google security researcher Chris Evans reported that data can be read across domains by injecting bogus CSS selectors into a target site and then retrieving the data using JavaScript APIs. If an attacker can inject opening and closing portions of a CSS selector into points A and B of a target pag...

nsCSSValue::Array index integer overflow — Mozilla

Security researcher J23 reported via TippingPoint's Zero Day Initiative that an array class used to store CSS values contained an integer overflow vulnerability. The 16 bit integer value used in allocating the size of the array could overflow, resulting in too small a memory buffer being created...

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...

UTF-8 URL stack buffer overflow — Mozilla

Justin Schuh and Tom Cross of the IBM X-Force and Peter Williams of IBM Watson Labs reported errors in Mozilla URL parsing routines. These errors could be exploited using a specially crafted UTF-8 URL in a hyperlink which could overflow a stack buffer and allow an attacker to execute arbitrary co...

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 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 78.10.1 — Mozilla

The Mozilla Maintenance Service granted SERVICESTART access to BUILTIN|Users which, in a domain network, grants normal remote users access to start or stop the service. This could be used to prevent the browser update service from operating if an attacker spammed the 'Stop' command; but also...

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...

Miscellaneous memory safety hazards (rv:45.0 / rv:38.7) — Mozilla

Mozilla developers 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 exploited to run...

NSS and NSPR memory corruption issues — Mozilla

Mozilla engineers Tyson Smith and David Keeler reported a use-after-poison and buffer overflow in the ASN.1 decoder in Network Security Services NSS. These issues were in octet string parsing and were found through fuzzing and code inspection. If these issues were triggered, they would lead to a...

Certificate verification bypass through the HTTP/2 Alt-Svc header — Mozilla

Security researcher Muneaki Nishimura discovered a flaw in the Mozilla's HTTP Alternative Services implementation. If an Alt-Svc header is specified in the HTTP/2 response, SSL certificate verification can be bypassed for the specified alternate server. As a result of this, warnings of invalid SS...

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...

Memory corruption crashes in Off Main Thread Compositing — Mozilla

Security researcher Abhishek Arya Inferno of the Google Chrome Security Team used the Address Sanitizer tool to discover two memory corruption crashes during 2D graphics rendering due to problems in Off Main Thread Compositing. These crashes are potentially exploitable...

CSP leaks redirect data via violation reports — Mozilla

Security researcher Muneaki Nishimura discovered that Content Security Policy CSP violation reports triggered by a redirect did not remove path information as required by the CSP specification. This potentially reveals information about the redirect that would not otherwise be known to the origin...

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...

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...

Miscellaneous memory safety hazards (rv:26.0 / rv:24.2) — 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...

Miscellaneous Network Security Services (NSS) vulnerabilities — Mozilla

Mozilla has updated the version of Network Security Services NSS library used in Mozilla projects to NSS 3.15.3 with the exception of ESR17-based releases, which have been updated to NSS 3.14.5. This addresses several moderate to critical rated networking security issues...

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...

Buffer Overflow in Canvas — Mozilla

Security researcher miaubiz used the Address Sanitizer tool to discover a buffer overflow in Canvas when specific bad height and width values were given through HTML. This could lead to a potentially exploitable crash...

Improper character decoding in HZ-GB-2312 charset — Mozilla

Security researcher Masato Kinugawa found when HZ-GB-2312 charset encoding is used for text, the "" character will destroy another character near the chunk delimiter. This can lead to a cross-site scripting XSS attack in pages encoded in HZ-GB-2312...

Heap memory corruption issues found using Address Sanitizer — Mozilla

Security researcher Atte Kettunen from OUSPG reported several heap memory corruption issues found using the Address Sanitizer tool. These issues are potentially exploitable, allowing for remote code execution...

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...

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...

BOM characters, low surrogates stripped from JavaScript before execution — Mozilla

Microsoft developer Dave Reed reported that certain BOM characters are stripped from JavaScript code before it is executed. This can lead to code, which would otherwise be treated as part of a quoted string, to be executed. The issue could potentially be used by an attacker to bypass or evade...

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...

Localstore.rdf XML injection through XULDocument.persist() — Mozilla

XULDocument.persist did not validate the attribute name, allowing an attacker to inject XML into localstore.rdf that would be read and acted upon at startup. This could include JavaScript commands that would be run with the permissions of the browser...

Security Vulnerabilities fixed in Thunderbird 128.1 — Mozilla

Select options could obscure the fullscreen notification dialog. This could be used by a malicious site to perform a spoofing attack. Insufficient checks when processing graphics shared memory could have led to memory corruption. This could be leveraged by an attacker to perform a sandbox escape....

Security Vulnerabilities fixed in Thunderbird 115.14 — Mozilla

Insufficient checks when processing graphics shared memory could have led to memory corruption. This could be leveraged by an attacker to perform a sandbox escape. Incomplete WebAssembly exception handing could have led to a use-after-free. Editor code failed to check an attribute value. This cou...

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 68 — Mozilla

When an inner window is reused, it does not consider the use of document.domain for cross-origin protections. If pages on different subdomains ever cooperatively use document.domain, then either page can abuse this to inject script into arbitrary pages on the other subdomain, even those that did...

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,...

Incorrect icon displayed on permissions notifications — Mozilla

Security researcher Tim McCormack reported that when a page requests a series of permissions in a short timespan, the resulting permission notifications can show the icon for the wrong permission request. This can lead to user confusion and inadvertent consent given when a user is prompted by web...

Linux video memory DOS with Intel drivers — Mozilla

Security researcher Ucha Gobejishvili reported a denial of service DOS attack when doing certain WebGL operations in a canvas requiring an unusually large amount buffer to be allocated from video memory. This resulted in memory resource exhaustion with some Intel video cards, requiring the comput...

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...

Mozilla Content Security Policy allows for asterisk wildcards in violation of CSP specification — Mozilla

Mozilla security engineer Christoph Kerschbaumer reported a discrepancy in Mozilla's implementation of Content Security Policy and the CSP specification. The specification states that blob:, data:, and filesystem: URLs should be excluded in case of a wildcard when matching source expressions but...

Out-of-bounds write with Updater and malicious MAR file — Mozilla

Security researcher Holger Fuhrmannek reported that if the Updater opens a MAR format file with a specially crafted name, an out-of-bounds write will occur. This can lead to a potentially exploitable crash but requires that the malicious MAR format file be present on the local system and the...

Use-after-free when using the Fluendo MP3 GStreamer plugin — Mozilla

Security researcher Aki Helin reported a use-after-free when playing certain MP3 format audio files on the web using the Fluendo MP3 plugin for GStreamer on Linux. This is due to a flaw in handling certain MP3 files by the plugin and its interaction with Mozilla code. This can lead to a potential...

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...

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...

Firefox for Android addressbar suppression — Mozilla

Security researcher Juho Nurminen reported that on Firefox for Android, when the addressbar has been scrolled off screen, an attacker can prevent it from rendering again through the use of script interacting DOM events. This allows an attacker to present a fake addressbar to the user, possibly...

Content Security Policy for data: documents not preserved by session restore — Mozilla

Security researcher Nicolas Golubovic reported that the Content Security Policy CSP of data: documents was not saved as part of session restore. If an attacker convinced a victim to open a document from a data: URL injected onto a page, this can lead to a Cross-Site Scripting XSS attack. The targ...

Script execution in HTML mail replies — Mozilla

Security researcher Fabián Cuchietti discovered that it was possible to bypass the restriction on JavaScript execution in mail by embedding an with a data: URL within a message. If the victim replied or forwarded the mail after receiving it, quoting it "in-line" using Thunderbird's HTML mail...

Incorrect use of discarded images by RasterImage — Mozilla

Fredrik 'Flonka' Lönnqvist discovered an issue with image decoding in RasterImage caused by continued use of discarded images. This could allow for the writing to unowned memory and a potentially exploitable crash...

Writing to cycle collected object during image decoding — Mozilla

Mozilla community member Ezra Pool reported a potentially exploitable crash on extremely large pages. This was caused when a cycle collected image object was released on the wrong thread during decoding, creating a race condition...

Use-after-free in Animation Manager during stylesheet cloning — Mozilla

Security researcher Abhishek Arya Inferno of the Google Chrome Security Team used the Address Sanitizer tool to discover a use-after-free problem in the Animation Manager during the cloning of stylesheets. This can lead to a potentially exploitable crash...