Mozilla Firefox — свободный браузер на движке Gecko

When a new Firefox profile is created on 64-bit Windows installations, the sandbox for 64-bit NPAPI plugins is not enabled by default. Note: This issue only affects 64-bit Windows. 32-bit Windows and other operating systems are unaffected. This vulnerability affects Firefox < 50.

An error in argument length checking in JavaScript, leading to potential integer overflows or other bounds checking issues. This vulnerability affects Thunderbird < 45.5, Firefox ESR < 45.5, and Firefox < 50.

A buffer overflow was found during UTF8 to Unicode string conversion within JavaScript with extremely large amounts of data. This vulnerability requires the use of a malicious or vulnerable legacy extension in order to occur. This vulnerability affects Thunderbird ESR < 52.8, Thunderbird < 52.8, and Firefox ESR < 52.8.

A use-after-free vulnerability with the frameloader during tree reconstruction while regenerating CSS layout when attempting to use a node in the tree that no longer exists. This results in a potentially exploitable crash. This vulnerability affects Firefox < 54, Firefox ESR < 52.2, and Thunderbird < 52.2.

WebExtensions could use the "mozAddonManager" API by modifying the CSP headers on sites with the appropriate permissions and then using host requests to redirect script loads to a malicious site. This allows a malicious extension to then install additional extensions without explicit user permission. This vulnerability affects Firefox < 51.

A buffer overflow can occur when manipulating Accessible Rich Internet Applications (ARIA) attributes within the DOM. This results in a potentially exploitable crash. This vulnerability affects Thunderbird < 52.3, Firefox ESR < 52.3, and Firefox < 55.

Certain response codes in FTP connections can result in the use of uninitialized values for ports in FTP operations. This vulnerability affects Firefox < 52, Firefox ESR < 45.8, Thunderbird < 52, and Thunderbird < 45.8.

During TLS 1.2 exchanges, handshake hashes are generated which point to a message buffer. This saved data is used for later messages but in some cases, the handshake transcript can exceed the space available in the current buffer, causing the allocation of a new buffer. This leaves a pointer pointing to the old, freed buffer, resulting in a use-after-free when handshake hashes are then calculated afterwards. This can result in a potentially exploitable crash. This vulnerability affects Firefox < 56, Firefox ESR < 52.4, and Thunderbird < 52.4.

JIT-spray targeting asm.js combined with a heap spray allows for a bypass of ASLR and DEP protections leading to potential memory corruption attacks. This vulnerability affects Firefox < 52, Firefox ESR < 45.8, Thunderbird < 52, and Thunderbird < 45.8.

If a server sends two Strict-Transport-Security (STS) headers for a single connection, they will be rejected as invalid and HTTP Strict Transport Security (HSTS) will not be enabled for the connection. This vulnerability affects Firefox < 55.