Mozilla: >> Firefox Security Vulnerabilities
Sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.
CVSS Score
9.6
EPSS Score
0.003
Published
2026-06-16
Sandbox escape due to incorrect boundary conditions in the Networking component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.
CVSS Score
9.6
EPSS Score
0.003
Published
2026-06-16
Idira Identity Browser Extension (Chrome, Firefox, and Edge builds) versions prior to 26.8.1 exhibit an origin validation flaw within its internal web-page verification routines. If an authenticated user navigates to a specially crafted webpage, this interaction could potentially allow a remote attacker to trigger unauthorized application interaction or execution parameters within the context of that authenticated browser session. CyberArk Security Bulletin: CA26-21
CVSS Score
8.4
EPSS Score
0.002
Published
2026-06-11
Incorrect boundary conditions in the Graphics: Text component. This vulnerability was fixed in Firefox 151.0.3.
CVSS Score
7.5
EPSS Score
0.003
Published
2026-06-02
JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 151.0.3.
CVSS Score
4.3
EPSS Score
0.002
Published
2026-06-02
Firefox for iOS Reader View replaced page content in its HTML template before replacing other internal placeholders. A malicious page could include a placeholder string that was later substituted with JSON-LD data, potentially resulting in arbitrary JavaScript execution. This vulnerability was fixed in Firefox for iOS 151.2.
CVSS Score
5.4
EPSS Score
0.002
Published
2026-06-01
Firefox for iOS Reader View did not properly escape HTML tags in JSON-LD metadata. A malicious page could inject markup that changed Reader View behavior and leaked sensitive URL parameters. These parameters could then be used to access internal pages, potentially resulting in arbitrary JavaScript execution in an internal origin. This vulnerability was fixed in Firefox for iOS 151.2.
CVSS Score
5.4
EPSS Score
0.002
Published
2026-06-01
Firefox for iOS displayed specially crafted right-to-left (RTL) and internationalized domain names (IDNs) incorrectly in link preview UI surfaces. A crafted RTL hostname could visually reorder portions of the displayed domain, causing attacker-controlled sites to appear as trusted origins. This vulnerability was fixed in Firefox for iOS 151.1.
CVSS Score
5.4
EPSS Score
0.002
Published
2026-05-25
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