PT-2026-27392 · Mozilla · Firefox+2

Sajeeb Lohani · Published 2026-03-24 · Updated 2026-03-24 · CVE-2026-4693

Positive Technologies · (AI Summary)

CVSS v3.1

7.5

High

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

Name of the Vulnerable Software and Affected Versions Firefox versions prior to 149 Firefox ESR versions prior to 115.34 Firefox ESR versions prior to 140.9 Thunderbird versions prior to 149 Thunderbird versions prior to 140.9

Description An issue exists due to incorrect boundary conditions within the Audio/Video: Playback component. This could potentially allow for unexpected behavior during audio or video playback.

Recommendations Update Firefox to version 149 or later. Update Firefox ESR to version 115.34 or later. Update Firefox ESR to version 140.9 or later. Update Thunderbird to version 149 or later. Update Thunderbird to version 140.9 or later.

Fix

Improper Check for Exceptional Conditions

Weakness Enumeration

CWE-754

Related Identifiers

CVE-2026-4693

Affected Products

Firefox

Firefox Esr

Thunderbird

References · 7

• https://nvd.nist.gov/vuln/detail/CVE-2026-4693 · Security Note
• https://mozilla.org/security/advisories/mfsa2026-23 · Vendor Advisory
• https://mozilla.org/security/advisories/mfsa2026-21 · Vendor Advisory
• https://mozilla.org/security/advisories/mfsa2026-24 · Vendor Advisory
• https://mozilla.org/security/advisories/mfsa2026-22 · Vendor Advisory
• https://mozilla.org/security/advisories/mfsa2026-20 · Vendor Advisory
• https://bugzilla.mozilla.org/show_bug.cgi?id=2018102 · Note