The version of Firefox ESR installed on the remote macOS or Mac OS X host is prior to 140.12. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2026-58 advisory.

  - Memory safety bugs present in Firefox ESR 140.11, Thunderbird ESR 140.11, Firefox 151 and Thunderbird 151.
    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-2026-12327)

  - Use-after-free in the Networking: HTTP component. This vulnerability was fixed in Firefox 152, Firefox ESR     140.12, and Firefox ESR 115.37. (CVE-2026-12291)

  - Incorrect boundary conditions in the Web Audio component. This vulnerability was fixed in Firefox 152 and     Firefox ESR 140.12. (CVE-2026-12292)

  - Sandbox escape in the DOM: Navigation component. This vulnerability was fixed in Firefox 152, Firefox ESR     140.12, and Firefox ESR 115.37. (CVE-2026-12295)

  - Sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox 152     and Firefox ESR 140.12. (CVE-2026-12296)

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

Detections

Analytics

Mozilla Firefox ESR < 140.12

critical Nessus Plugin ID 321195

Version 1.4

Version 1.3

Version 1.2

Version 1.1

Version 1.4 Jul 4, 2026, 4:43 PM CVSS metrics ("CVSSv3 score" set to 9.1) CVSS metrics ("CVSSv3 vector" set to "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N") CVSSv3 score source (changed from "CVE-2026-12297" to "CVE-2026-12315") Plugin Feed: 202607041643
Version 1.3 Jun 26, 2026, 4:08 PM Plugin metadata (Add IAVM Info) Plugin Feed: 202606261608
Version 1.2 Jun 20, 2026, 5:45 PM CVSS metrics ("CVSSv3 score" set to 9.6) CVSS metrics ("CVSSv3 vector" set to "CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H") CVSSv3 score source (set to "CVE-2026-12297") Plugin Feed: 202606201745
Version 1.1 Jun 16, 2026, 9:15 PM New Plugin Feed: 202606162115