Mozilla

Security Vulnerabilities fixed in Thunderbird 140.15

MFSA2026-87 Sep 1, 2026 Source: Vendor

Imported from Mozilla security advisory MFSA2026-87. Draft.

Source of record The credited names below are quoted verbatim from the vendor's own advisory: https://www.mozilla.org/en-US/security/advisories/mfsa2026-87/

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Credited

20 lines

Showing 1–20 of 20

CVE-2026-84639 BR2026-0000-044016 unclaimed

High: Uninitialized memory in MIME parsing

Credited as Ramesh Adhikari

CVE-2026-84639 BR2026-0000-044017 unclaimed

High: Uninitialized memory in MIME parsing

Credited as Dr. Faruk Kazi (CoE-CNDS Lab, VJTI, Mumbai, India)

CVE-2026-84640 BR2026-0000-044018 unclaimed

Medium: One byte overflow read in mail parser

Credited as Ramesh Adhikari

CVE-2026-84640 BR2026-0000-044019 unclaimed

Medium: One byte overflow read in mail parser

Credited as Dr. Faruk Kazi (CoE-CNDS Lab, VJTI, Mumbai, India)

CVE-2026-84641 BR2026-0000-044020 unclaimed

Low: Information disclosure due to malicious IMAP server response

Credited as ABDULAZIZ ALASAIQAH

CVE-2026-75874 BR2026-0000-044021 unclaimed

High: Sandbox escape in the Remote Settings Client component

Credited as crixer

CVE-2026-16365 BR2026-0000-044022 unclaimed

High: Privilege escalation in the DOM: Workers component

Credited as Khanh Nguyen

CVE-2026-84119 BR2026-0000-044023 unclaimed

High: Sandbox escape due to use-after-free in the DOM: Navigation component

Credited as Yaqoub Aldurayhim

CVE-2026-84120 BR2026-0000-044024 unclaimed

High: Use-after-free in the Audio/Video component

Credited as Ukyo Akai

CVE-2026-84121 BR2026-0000-044025 unclaimed

High: Sandbox escape due to use-after-free in the DOM: Security component

Credited as Yaqoub Aldurayhim

CVE-2026-84122 BR2026-0000-044026 unclaimed

High: Use-after-free in the Audio/Video component

Credited as Hyeonjun Ahn

CVE-2026-84124 BR2026-0000-044027 unclaimed

High: Use-after-free in the DOM: Core & HTML component

Credited as Hyeonjun Ahn

CVE-2026-16371 BR2026-0000-044028 unclaimed

Moderate: Privilege escalation in the DOM: Navigation component

Credited as Steven Julian

CVE-2026-84131 BR2026-0000-044029 unclaimed

Moderate: Privilege escalation due to invalid pointer in the Graphics component

Credited as navapon

CVE-2026-84143 BR2026-0000-044030 unclaimed