SB2026043088 - Multiple vulnerabilities in Mozilla Thunderbird



SB2026043088 - Multiple vulnerabilities in Mozilla Thunderbird

Published: April 30, 2026

Security Bulletin ID SB2026043088
CSH Severity
High
Patch available
YES
Number of vulnerabilities 4
Exploitation vector Remote access
Highest impact Code execution

Breakdown by Severity

High 75% Medium 25%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 4 vulnerabilities.


1) Out-of-bounds read (CVE-ID: CVE-2026-7320)

CWE-ID: CWE-125 - Out-of-bounds read

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green


The vulnerability allows a remote attacker to disclose sensitive information.

The vulnerability exists due to incorrect boundary conditions in the Audio/Video component when processing media content. A remote attacker can cause the browser to process specially crafted media content to disclose sensitive information.


2) Buffer overflow (CVE-ID: CVE-2026-7322)

CWE-ID: CWE-119 - Memory corruption

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber


The vulnerability allows a remote attacker to execute arbitrary code.

The vulnerability exists due to memory corruption when processing crafted web content. A remote attacker can trigger memory safety bugs to execute arbitrary code.


3) Buffer overflow (CVE-ID: CVE-2026-7323)

CWE-ID: CWE-119 - Memory corruption

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber


The vulnerability allows a remote attacker to execute arbitrary code.

The vulnerability exists due to memory corruption when rendering web content. A remote attacker can trigger memory corruption using specially crafted web content to execute arbitrary code.


4) Buffer overflow (CVE-ID: CVE-2026-7324)

CWE-ID: CWE-119 - Memory corruption

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber


The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error when processing HTML content. A remote attacker can trick the victim into visiting a specially crafted website, trigger memory corruption and execute arbitrary code on the target system.


Remediation

Install update from vendor's website.