Same-origin policy bypass in the CSS Parsing and Computation component. This vulnerability affects Firefox < 148.0.2.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - Same-origin policy bypass in the CSS Parsing and Computation component. This vulnerability affects Firefox     < 148.0.2. (CVE-2026-3846)

Note that Nessus relies on the presence of the package as reported by the vendor.

The version of FreeBSD installed on the remote host is prior to tested version. It is, therefore, affected by a vulnerability as referenced in the e1e40d50-1de2-11f1-8aff-b42e991fc52e advisory.

    https://bugzilla.mozilla.org/show_bug.cgi?id=2018400 reports:
    Same-origin policy bypass in the CSS Parsing and                 Computation component.

Tenable has extracted the preceding description block directly from the FreeBSD security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The version of Firefox installed on the remote macOS or Mac OS X host is prior to 148.0.2. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2026-19 advisory.

  - Memory safety bugs present in Firefox 148.0.2. Some of these bugs showed evidence of memory corruption and     we presume that with enough effort some of these could have been exploited to run arbitrary code.
    (CVE-2026-3847)

  - Heap buffer overflow in the Audio/Video: Playback component in Firefox for Android. This vulnerability     affects Firefox < 148.0.2. (CVE-2026-3845)

  - Same-origin policy bypass in the CSS Parsing and Computation component. This vulnerability affects Firefox     < 148.0.2. (CVE-2026-3846)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The version of Firefox installed on the remote Windows host is prior to 148.0.2. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2026-19 advisory.

  - Memory safety bugs present in Firefox 148.0.2. Some of these bugs showed evidence of memory corruption and     we presume that with enough effort some of these could have been exploited to run arbitrary code.
    (CVE-2026-3847)

  - Heap buffer overflow in the Audio/Video: Playback component in Firefox for Android. This vulnerability     affects Firefox < 148.0.2. (CVE-2026-3845)

  - Same-origin policy bypass in the CSS Parsing and Computation component. This vulnerability affects Firefox     < 148.0.2. (CVE-2026-3846)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Severity
302204	Linux Distros Unpatched Vulnerability : CVE-2026-3846	Nessus	Misc.	medium
302005	FreeBSD : Firefox -- Same-origin policy bypass (e1e40d50-1de2-11f1-8aff-b42e991fc52e)	Nessus	FreeBSD Local Security Checks	medium
301761	Mozilla Firefox < 148.0.2	Nessus	MacOS X Local Security Checks	high
301760	Mozilla Firefox < 148.0.2	Nessus	Windows	high

Detections

Analytics

CVE-2026-3846

medium

Tenable Plugins

medium

medium

high

high