Is CVE-2026-118003 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-118003 being exploited in the wild.

How severe is CVE-2026-118003?

Informational severity, published 27 October 2026.

Which products and versions are affected?

Mozilla Firefox before 159; Mozilla Firefox ESR before 153.6.

Is there a fix for CVE-2026-118003?

Yes: fixed in Firefox 159, Firefox ESR 153.6. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-118003 attacked?

It is attacked over the network.

Am I affected by CVE-2026-118003?

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-2026-118003: Mozilla Firefox information disclosure in DNS networking

CVE-2026-118003 · Severity: info · Published 2026-10-27

Firefox, a web browser used by millions to access the internet, contains an information disclosure vulnerability in its DNS networking component. An attacker could exploit this flaw to leak sensitive information during DNS operations. The vulnerability has been patched in Firefox 159 and Firefox ESR 153.6.

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

Quick answers

Is CVE-2026-118003 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-118003 being exploited in the wild.
How severe is CVE-2026-118003?: Informational severity, published 27 October 2026.
Which products and versions are affected?: Mozilla Firefox before 159; Mozilla Firefox ESR before 153.6.
Is there a fix for CVE-2026-118003?: Yes: fixed in Firefox 159, Firefox ESR 153.6. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-118003 attacked?: It is attacked over the network.
Am I affected by CVE-2026-118003?: 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 159, Firefox ESR 153.6

Technical details

The vulnerability is an information disclosure issue in Firefox's Networking: DNS component. The specific attack vector and preconditions are not detailed in the available advisory content, but the flaw allows unintended information leakage. Mozilla has issued a fix in Firefox 159 and Firefox ESR 153.6.

Affected products

Mozilla Firefox before 159
Mozilla Firefox ESR before 153.6

Timeline

2026-10-27: disclosed

References

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