PT-2026-40046 · Mozilla+1 · Firefox+1

Andrew Mccreight + 1 · Published 2026-05-12 · Updated 2026-06-02 · CVE-2026-8401

Positive Technologies (AI Summary)

CVSS v3.1

9.8

Critical

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions Firefox versions prior to 150.0.3 Firefox ESR versions prior to 115.36 Firefox ESR versions prior to 140.11

Description A sandbox escape exists in the Profile Backup component. A sandbox is a security mechanism for separating running programs, ensuring that code in a sandbox cannot access resources outside of it.

Recommendations Update to version 150.0.3. Update to ESR version 115.36. Update to ESR version 140.11.

Fix

DoS

Protection Mechanism Failure

Weakness Enumeration

CWE-693

Related Identifiers

ALSA-2026:21378

ALSA-2026:21380

ALSA-2026:21381

ALSA-2026:21382

ALSA-2026:22325

ALSA-2026:22643

CVE-2026-8401

OESA-2026-2392

OESA-2026-2393

OESA-2026-2394

OPENSUSE-SU-2026:10813-1

OPENSUSE-SU-2026:10864-1

Affected Products

Firefox

Rocky Linux

References · 125

• https://nvd.nist.gov/vuln/detail/CVE-2026-8401 · Security Note
• https://errata.almalinux.org/9/ALSA-2026-21381.html · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-8401 · Vendor Advisory
• https://osv.dev/vulnerability/OESA-2026-2394 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-8946 · Security Note
• https://errata.almalinux.org/9/ALSA-2026-21378.html · Vendor Advisory
• https://mozilla.org/security/advisories/mfsa2026-45 · Vendor Advisory
• https://osv.dev/vulnerability/openSUSE-SU-2026:10864-1 · Vendor Advisory
• https://mozilla.org/security/advisories/mfsa2026-51 · Vendor Advisory
• https://linux.oracle.com/errata/ELSA-2026-21382.html · Vendor Advisory
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-8401 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-8954 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2026-8956 · Security Note
• https://mozilla.org/security/advisories/mfsa2026-48/#CVE-2026-8401 · Vendor Advisory
• https://osv.dev/vulnerability/ALSA-2026:22643 · Vendor Advisory