CVE-2026-9308

5.4 MEDIUM 0.2% exploit odds Fix listed XSS Browser & mail

What it is

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.

At a glance

Exploitability: Can be exploited over the network without logging in, but needs a user to act. Limited direct impact.
Exploit odds: 0.2% chance of exploitation in the next 30 days (EPSS).
Fix: A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

2026-06-01 13:16 UTC PublishedDisclosed publicly on CVE.org and NVD
2026-07-22 07:10 UTC Last updatedMost recent change to the record

Details

Published: 2026-06-01 13:16 UTC
Last modified: 2026-07-22 07:10 UTC
Exploit probability: 0.2% · EPSS, next 30 days
Weakness: CWE-79 · Cross-site scripting
Record status: Analyzed

Affected

Mozilla Firefox < 151.2

Attack profile CVSS 3.1 · 5.4

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: Required
Scope: Unchanged
Confidentiality: Low
Integrity: Low
Availability: None

Raw vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N

Download Square Reddit

Fix and advisories

https://www.mozilla.org/security/advisories/mfsa2026-53/

References

NVD record · CVE.org record