Mozilla: Security Vulnerabilities
Firefox for iOS hosted Reader mode on an unauthenticated local web server, allowing another application on the same device to request arbitrary URLs and receive the response rendered with the signed-in user's cookies. This vulnerability was fixed in Firefox for iOS 151.0.
CVSS Score
6.5
EPSS Score
0.002
Published
2026-05-19
Memory safety bugs present in Firefox ESR 115.35, Firefox ESR 140.10 and Firefox 150. 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 was fixed in Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
CVSS Score
8.8
EPSS Score
0.003
Published
2026-05-19
Information disclosure in the IP Protection component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.
CVSS Score
7.5
EPSS Score
0.003
Published
2026-05-19
Information disclosure in the Graphics: WebGPU component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.
CVSS Score
7.5
EPSS Score
0.003
Published
2026-05-19
Denial-of-service due to invalid pointer in the Audio/Video: Web Codecs component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
CVSS Score
7.5
EPSS Score
0.004
Published
2026-05-19
Mitigation bypass in the DOM: Security component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.
CVSS Score
8.1
EPSS Score
0.003
Published
2026-05-19
Privilege escalation in the Security component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
CVSS Score
8.8
EPSS Score
0.003
Published
2026-05-19
Same-origin policy bypass in the Networking: JAR component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.
CVSS Score
6.5
EPSS Score
0.001
Published
2026-05-19
Privilege escalation in the WebRTC: Audio/Video component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.
CVSS Score
8.8
EPSS Score
0.003
Published
2026-05-19
Memory safety bugs present in Firefox 150. 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 was fixed in Firefox 151 and Thunderbird 151.
CVSS Score
8.8
EPSS Score
0.003
Published
2026-05-19