Multiple serious vulnerabilities have been found in Mozilla Firefox. Malicious users can exploit these vulnerabilities to bypass security restrictions, inject arbitrary code, elevate privileges, cause denial of service or obtain sensitive information.

Below is a complete list of vulnerabilities

1. Memory safety bugs can be exploited to run arbitrary code;
2. Mozilla Maintenance Service updater can be exploited locally via specially crafted file to delete arbitrary files and possibly to escalate privileges; (Windows)
3. An unknown vulnerability in Firefox for Android can be exploited remotely via previously installed malicious application to obtain sensitive information; (Android versions earlier than 5.0)
4. Improper objects handling in Service Workers can be exploited to cause denial of service or other unknown impacts;
5. An unknown vulnerability in Service Workers can be exploited via buffer overflow to cause a denial of service;
6. Unauthorized access to orientation data and motion sensors in Firefox for Android can be exploited via specially crafted JavaScript code to disclosure of user actions; (Android)
7. Improper handling of sizes can be exploited remotely via specially crafted web content to cause a denial of service;
8. Improper Content Security Policy (CSP) applying to web content can be exploited to conduct XSS attack via a crafted web site;
9. An unknown vulnerability in API for web extensions can be exploited remotely via specially crafted web extension to conduct XSS and to inject content into legitimate extensions;
10. An unknown vulnerability can be exploited remotely via specially crafted malicious page to arbitrary code execution;
11. Improper events processing in the Firefox Health Report can be exploited via specially crafted content document for the remote-report iframe to inject web content into the Firefox Health Report iframe;

Technical details

Vulnerability (2) caused by Mozilla Maintenance Service privileged system access.

Vulnerability (3) allows malicious user access content provider permissions for Firefox in order to read data includes browser history and locally saved passwords. It occurs when a list of permissions is defined to match those that Firefox uses for content providers and bypasses signature protections.

Vulnerability (4) caused by keeping active ServiceWorkerInfo object after its registration finishing. We’ll get use-after-free as result.

Vulnerability (5) caused by race condition in the ServiceWorkerManager.

Vulnerability (7) caused by improper handling of CENC offsets and the sizes tables in the libstagefright library. It can be exploited through the buffer overflow.

Vulnerability (8) caused by sending CSP with the multipart/x-mixed-replace MIME type.

Vulnerability (9) related to chrome.tabs.update API and allows navigation to JavaScript URLs without additional permissions. It is possible to inject content into legitimate extensions if they load content within browser tabs.

Vulnerability (10) related to JavaScript .watch() method which could be used to overflow the 32-bit generation count of the underlying HashMap. As result we’ll get write to an invalid entry. The overflow require a user to keep a malicious page open for the duration of the attack.

Vulnerability (11) allows attacker to change the sharing preferences of a user by firing the appropriate events at its containing page.

Mozilla Firefox versions earlier than 46
Mozilla Firefox ESR versions earlier than 38.8  
Mozilla Firefox ESR 45 versions earlier than 45.1

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