PT-2026-21737 · Mozilla · Thunderbird+1

Published 2026-02-24 · Updated 2026-02-26 · CVE-2026-2804

Positive Technologies (AI Summary)

CVSS v2.0

6.4

Medium

Base vector

AV:N/AC:L/Au:N/C:P/I:P/A:N

Name of the Vulnerable Software and Affected Versions Firefox versions prior to 148 Thunderbird versions prior to 148

Description A use-after-free issue exists in the JavaScript: WebAssembly component. This condition may lead to unpredictable behavior or allow for arbitrary code execution.

Recommendations Update Firefox to version 148 or later. Update Thunderbird to version 148 or later.

Fix

Use After Free

Weakness Enumeration

CWE-416

Related Identifiers

BDU:2026-06187

CVE-2026-2804

OPENSUSE-SU-2026:10257-1

Affected Products

Firefox

Thunderbird

References · 72

• https://mozilla.org/en-US/security/advisories/mfsa2026-13 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-2804 · Security Note
• https://cve.org/CVERecord?id=CVE-2026-2804 · Security Note
• https://bdu.fstec.ru/vul/2026-06187 · Security Note
• https://mozilla.org/security/advisories/mfsa2026-16 · Vendor Advisory
• https://mozilla.org/security/advisories/mfsa2026-13 · Vendor Advisory
• https://mozilla.org/en-US/security/advisories/mfsa2026-16 · Vendor Advisory
• https://mozilla.org/en-US/security/advisories/mfsa2026-13/#CVE-2026-2804 · Vendor Advisory
• https://mozilla.org/en-US/security/advisories/mfsa2026-16/#CVE-2026-2804 · Vendor Advisory
• https://wiki.astralinux.ru/astra-linux-se18-bulletin-2026-0423SE18MD · Vendor Advisory
• https://wiki.astralinux.ru/astra-linux-se17-bulletin-2026-0421SE17 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2026-2804 · Vendor Advisory
• https://wiki.astralinux.ru/astra-linux-se47-bulletin-2026-0518SE47 · Vendor Advisory
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-2804 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2026-2804 · Vendor Advisory