CVE-2025-13019 Same-origin policy bypass in the DOM: Workers component

High 8.1 Published Updated

Attackers can bypass the same-origin policy in Firefox and Thunderbird, potentially accessing cross-origin data.

Exploited in the wild
Not known
Login needed
Not needed
Attackable
Over the internet
Victim action needed
A user has to click or open something
Fix
Available

What is CVE-2025-13019?

CVE-2025-13019 is a high-severity vulnerability in Mozilla Firefox, published on 11 Nov 2025. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

Official description

Same-origin policy bypass in the DOM: Workers component. This vulnerability was fixed in Firefox 145, Firefox ESR 140.5, Thunderbird 145, and Thunderbird 140.5.

Weakness: CWE-942

Which versions are affected by CVE-2025-13019?

It affects 1 product.

Products include Mozilla Firefox.

How do I fix CVE-2025-13019?

Upgrade to a fixed version.

Is CVE-2025-13019 being exploited?

There is no known exploitation of CVE-2025-13019 in the wild and no public exploit code.

All Mozilla Firefox vulnerabilities

Sources

Also known as DEBIAN-CVE-2025-13019, GHSA-mv5g-cf64-38cv, UBUNTU-CVE-2025-13019.

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