CVE-2025-0237 WebChannel APIs susceptible to confused deputy attack

What is CVE-2025-0237?

CVE-2025-0237 is a medium-severity vulnerability in Mozilla Firefox, published on 7 Jan 2025. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

The WebChannel API, which is used to transport various information across processes, did not check the sending principal but rather accepted the principal being sent. This could have led to privilege escalation attacks. This vulnerability was fixed in Firefox 134, Firefox ESR 128.6, Thunderbird 134, and Thunderbird 128.6.

Weakness: CWE-863

Which versions are affected by CVE-2025-0237?

It affects 2 products.

Products include Mozilla Firefox, Mozilla Thunderbird.

How do I fix CVE-2025-0237?

Upgrade to a fixed version.

Is CVE-2025-0237 being exploited?

There is no known exploitation of CVE-2025-0237 in the wild and no public exploit code.

Other vulnerabilities in Mozilla Firefox

• CVE-2019-11708 Mozilla Firefox and Thunderbird Sandbox Escape Exploited Critical 10.0
• CVE-2010-3765 Mozilla Multiple Products Remote Code Execution Exploited Critical 9.8
• CVE-2022-26486 Mozilla Firefox Use-After-Free Exploited Critical 9.6
• CVE-2022-26485 Mozilla Firefox Use-After-Free Exploited High 8.8
• CVE-2019-11707 Mozilla Firefox and Thunderbird Type Confusion Exploited High 8.8

All Mozilla Firefox vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2025-0237, GHSA-2776-h8x3-vrr7, UBUNTU-CVE-2025-0237.