CVE-2026-15719 in Firefox
We are aware that exploit code for this is public however we are not aware of any attacks in the wild abusing this flaw. This vulnerability was fixed in Firefox 152.0.6.
Quick answer
Mozilla Firefox should be reviewed and updated if it matches the affected versions. The recommended fix is to apply the vendor-supported patched version or the mitigation steps below, then retest the public website with Fixnx.
Who is affected
Affected versions
- Firefox before 152.0.6
Fixed versions
- Firefox 152.0.6 or later
How to fix it
CVE-2026-15719 affects Firefox. In simple terms, the affected software may be used in an unsafe way. Fix it by updating to Firefox 152.0.6 or later. If this system is online or used by admins, treat the fix as important.
- Find every place where Firefox is installed or used.
- Check if the version matches: Firefox before 152.0.6.
- Update or apply the vendor fix: Firefox 152.0.6 or later.
- If you cannot update today, allow only trusted users and trusted networks.
- Turn off the affected feature or plugin if the vendor says that is safe to do.
- Check logs for crashes, strange requests, new admin actions, or unexpected access.
- Change secrets or passwords if you think data or admin access may have been exposed.
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Verify the fix
- Confirm the installed version or mitigation matches: Firefox 152.0.6 or later.
- Confirm the affected feature is no longer exposed to untrusted users.
- Run the affected workflow again and make sure it still works.
- Review logs again after the fix for repeated suspicious activity.
- Run a new Fixnx scan if this software is part of a public website.
- Save the advisory link and proof of the fix in your change record.
Related categories
Trusted references
FAQ
What is affected by CVE-2026-15719?
Mozilla Firefox versions listed as affected should be reviewed: Firefox before 152.0.6.
What should I fix first?
Start with internet-facing sites, admin panels, login flows, plugins, themes, modules, packages, and systems that process user-controlled input or sensitive data.
How do I confirm the fix worked?
Apply the patched version or mitigation, clear caches where relevant, retest the affected workflow, and run a new Fixnx scan to verify public website exposure signals.
How are Fixnx security risk categories chosen?
Fixnx keeps one canonical risk page and assigns only broad, relevant categories such as ecosystem, technology area, or vulnerability class.