Is CVE-2026-92035 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-92035 being exploited in the wild.

How severe is CVE-2026-92035?

Critical severity, with a CVSS score of 9.6, published 15 September 2026.

Which products and versions are affected?

Mozilla Firefox before 156; Mozilla Firefox ESR before 153.3; Mozilla Thunderbird before 153.3.

Is there a fix for CVE-2026-92035?

A patch was published on 2026-09-15: Firefox 156, Firefox ESR 153.3, Thunderbird 156, and Thunderbird 153.3 released with fix Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-92035 attacked?

It is attacked over the network, in a web application.

Am I affected by CVE-2026-92035?

Check whether you run Mozilla Firefox, Mozilla Firefox ESR or Mozilla Thunderbird at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-92035: Mozilla Firefox sandbox escape in Graphics component

CVE-2026-92035 · Severity: critical · CVSS 9.6 · Published 2026-09-15

Firefox's graphics processing engine contains a boundary condition flaw that allows attackers to escape the browser's security sandbox. An attacker can exploit this vulnerability through a malicious webpage to break out of the browser's isolated execution environment and potentially gain unauthorized access to the underlying system or user data.

Technologies: Mozilla Firefox, Mozilla Firefox ESR, Mozilla Thunderbird. Vendors: Mozilla.

Quick answers

Is CVE-2026-92035 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-92035 being exploited in the wild.
How severe is CVE-2026-92035?: Critical severity, with a CVSS score of 9.6, published 15 September 2026.
Which products and versions are affected?: Mozilla Firefox before 156; Mozilla Firefox ESR before 153.3; Mozilla Thunderbird before 153.3.
Is there a fix for CVE-2026-92035?: A patch was published on 2026-09-15: Firefox 156, Firefox ESR 153.3, Thunderbird 156, and Thunderbird 153.3 released with fix Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-92035 attacked?: It is attacked over the network, in a web application.
Am I affected by CVE-2026-92035?: Check whether you run Mozilla Firefox, Mozilla Firefox ESR or Mozilla Thunderbird at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

This is a sandbox escape vulnerability caused by incorrect boundary condition checks in Firefox's Graphics component. The flaw allows an attacker to break out of the browser's security sandbox through crafted graphics operations. The attack is triggered via network delivery of a malicious webpage (user interaction required to load the page). Exploitation enables arbitrary code execution with the privileges of the browser process, potentially leading to full system compromise. The vulnerability was fixed in Firefox 156, Firefox ESR 153.3, Thunderbird 156, and Thunderbird 153.3.

Affected products

Mozilla Firefox before 156
Mozilla Firefox ESR before 153.3
Mozilla Thunderbird before 156
Mozilla Thunderbird before 153.3

Timeline

2026-09-15: disclosed: CVE-2026-92035 published
2026-09-15: patched: Firefox 156, Firefox ESR 153.3, Thunderbird 156, and Thunderbird 153.3 released with fix

References

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