Is CVE-2026-124935 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-124935 being exploited in the wild.

How severe is CVE-2026-124935?

Informational severity, published 10 November 2026.

Which products and versions are affected?

Mozilla Firefox before 160; Mozilla Firefox ESR before 153.7.

Is there a fix for CVE-2026-124935?

Yes: fixed in Firefox 160, Firefox ESR 153.7. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-124935 attacked?

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

Am I affected by CVE-2026-124935?

Check whether you run Mozilla Firefox or Mozilla Firefox ESR 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-2026-124935: Mozilla Firefox undefined behavior in WebRTC Networking

CVE-2026-124935 · Severity: info · Published 2026-11-10

Firefox, a widely-used web browser, contains undefined behavior in its WebRTC networking component that could allow unpredictable browser behavior or crashes. This vulnerability was fixed in Firefox 160 and Firefox ESR 153.7. Users should update to the patched versions to protect against potential instability or exploitation.

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

Quick answers

Is CVE-2026-124935 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-124935 being exploited in the wild.
How severe is CVE-2026-124935?: Informational severity, published 10 November 2026.
Which products and versions are affected?: Mozilla Firefox before 160; Mozilla Firefox ESR before 153.7.
Is there a fix for CVE-2026-124935?: Yes: fixed in Firefox 160, Firefox ESR 153.7. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-124935 attacked?: It is attacked over the network, in a web application.
Am I affected by CVE-2026-124935?: Check whether you run Mozilla Firefox or Mozilla Firefox ESR 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.

How to fix

Fixed in: Firefox 160, Firefox ESR 153.7

Technical details

Undefined behavior in the WebRTC networking component can lead to unpredictable runtime behavior depending on compiler optimizations and execution context. The vulnerability affects Firefox versions prior to 160 and ESR versions prior to 153.7. While marked as informational severity, undefined behavior in memory-unsafe code can be a stepping stone to exploitation.

Affected products

Mozilla Firefox before 160
Mozilla Firefox ESR before 153.7

Timeline

2026-11-10: disclosed

References

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