Mozilla: >> Firefox >> 154.0.0 Security Vulnerabilities
Privilege escalation in the WebDriver BiDi component. This vulnerability was fixed in Firefox 155 and Thunderbird 155.
CVSS Score
8.8
EPSS Score
0.004
Published
2026-09-01
Site isolation issue in the DOM: Navigation component. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.
CVSS Score
9.8
EPSS Score
0.003
Published
2026-09-01
Use-after-free in the JavaScript: GC component. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.
CVSS Score
5.4
EPSS Score
0.003
Published
2026-09-01
Sandbox escape due to use-after-free in the DOM: Navigation component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.
CVSS Score
9.6
EPSS Score
0.003
Published
2026-09-01
Use-after-free in the Audio/Video component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.
CVSS Score
5.4
EPSS Score
0.002
Published
2026-09-01
Sandbox escape due to use-after-free in the DOM: Security component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.
CVSS Score
9.6
EPSS Score
0.003
Published
2026-09-01
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
0.14
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
0.14
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
0.019
Published
2014-01-26
Unspecified vulnerability in Oracle Java SE 6u65 and Java SE 7u45, when running on Firefox, allows remote attackers to affect confidentiality, integrity, and availability via unknown vectors related to Deployment.
CVSS Score
7.6
EPSS Score
0.054
Published
2014-01-15