Mozilla: >> Firefox >> 141.0 Security Vulnerabilities
Memory safety bugs present in Firefox 141 and Thunderbird 141. 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 < 142 and Thunderbird < 142.
CVSS Score
9.8
EPSS Score
0.001
Published
2025-08-19
An attacker was able to perform memory corruption in the GMP process which processes encrypted media. This process is also heavily sandboxed, but represents slightly different privileges from the content process. This vulnerability affects Firefox < 142, Firefox ESR < 115.27, Firefox ESR < 128.14, Firefox ESR < 140.2, Thunderbird < 142, Thunderbird < 128.14, and Thunderbird < 140.2.
CVSS Score
9.8
EPSS Score
0.001
Published
2025-08-19
Same-origin policy bypass in the Graphics: Canvas2D component. This vulnerability affects Firefox < 142, Firefox ESR < 115.27, Firefox ESR < 128.14, Firefox ESR < 140.2, Thunderbird < 142, Thunderbird < 128.14, and Thunderbird < 140.2.
CVSS Score
8.1
EPSS Score
0.0
Published
2025-08-19
Uninitialized memory in the JavaScript Engine component. This vulnerability affects Firefox < 142, Firefox ESR < 128.14, Firefox ESR < 140.2, Thunderbird < 142, Thunderbird < 128.14, and Thunderbird < 140.2.
CVSS Score
6.5
EPSS Score
0.001
Published
2025-08-19
Denial-of-service due to out-of-memory in the Graphics: WebRender component. This vulnerability affects Firefox < 142, Firefox ESR < 140.2, Thunderbird < 142, and Thunderbird < 140.2.
CVSS Score
7.5
EPSS Score
0.001
Published
2025-08-19
Spoofing issue in the Address Bar component. This vulnerability affects Firefox < 142 and Firefox ESR < 140.2.
CVSS Score
6.5
EPSS Score
0.0
Published
2025-08-19
Memory safety bugs present in Firefox ESR 140.1, Thunderbird ESR 140.1, Firefox 141 and Thunderbird 141. 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 < 142, Firefox ESR < 140.2, Thunderbird < 142, and Thunderbird < 140.2.
CVSS Score
8.1
EPSS Score
0.001
Published
2025-08-19
The HTTP/2 protocol does not consider the role of the TCP congestion window in providing information about content length, which makes it easier for remote attackers to obtain cleartext data by leveraging a web-browser configuration in which third-party cookies are sent, aka a "HEIST" attack.
CVSS Score
5.3
EPSS Score
0.013
Published
2016-09-06
The HTTPS protocol does not consider the role of the TCP congestion window in providing information about content length, which makes it easier for remote attackers to obtain cleartext data by leveraging a web-browser configuration in which third-party cookies are sent, aka a "HEIST" attack.
CVSS Score
5.3
EPSS Score
0.013
Published
2016-09-06
Cross-site scripting (XSS) vulnerability in clickstream.js in Y! Toolbar plugin for FireFox 3.1.0.20130813024103 for Mac, and 2.5.9.2013418100420 for Windows, allows remote attackers to inject arbitrary web script or HTML via a crafted URL that is stored by the victim.
CVSS Score
4.3
EPSS Score
0.003
Published
2014-01-26