PT-2026-21734 · Mozilla · Thunderbird+1

Kanaru Sato · Published 2026-02-24 · Updated 2026-03-01 · CVE-2026-2801

Positive Technologies (AI Summary)

CVSS v2.0

7.8

High

Base vector

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

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

Description An issue exists due to incorrect boundary conditions within the JavaScript: WebAssembly component. This could potentially lead to unexpected behavior or compromise.

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

Fix

Buffer Overflow

Improper Check for Exceptional Conditions

Weakness Enumeration

CWE-119

CWE-754

Related Identifiers

BDU:2026-06190

CVE-2026-2801

OPENSUSE-SU-2026:10257-1

Affected Products

Firefox

Thunderbird

References · 75

• https://mozilla.org/en-US/security/advisories/mfsa2026-13 · Vendor Advisory
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-2801 · Vendor Advisory
• https://mozilla.org/security/advisories/mfsa2026-16 · Vendor Advisory
• https://mozilla.org/en-US/security/advisories/mfsa2026-13/#CVE-2026-2801 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-2801 · Security Note
• https://mozilla.org/security/advisories/mfsa2026-13 · Vendor Advisory
• https://mozilla.org/en-US/security/advisories/mfsa2026-16 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2026-2801 · Vendor Advisory
• https://bdu.fstec.ru/vul/2026-06190 · Security Note
• https://safe-surf.ru/specialists/bulletins-nkcki/729331 · Security Note
• https://wiki.astralinux.ru/astra-linux-se18-bulletin-2026-0423SE18MD · Vendor Advisory
• http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-2801 · Security Note
• https://wiki.astralinux.ru/astra-linux-se17-bulletin-2026-0421SE17 · Vendor Advisory
• https://wiki.astralinux.ru/astra-linux-se47-bulletin-2026-0518SE47 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2026-2801 · Vendor Advisory